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SINFONI User Manual

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1. Parameter Range Default P2PP Label SEQ SPECDITH TF F Spectral dithering Hidden parameters SEQ ARC TF T Night Arc SEQ FLATFIELD TF F Night Flat field DPR CATG CALIB CALIB Data product category DPR TECH IFU IFU Data product technique DPR TYPE WAVE LAMP FLAT LAMP Data product type 12 4 Daytime Calibration Templates 15 The day time calibration observations are typically prepared by the staff astronomers with an automatic tool calobBuild which will scan the headers of the frames taken during the nights Based on this data it will then define and sort the required sequence of calibration exposures according to the SINFONI calibration plan It is not foreseen that users will use any of the day time calibration templates below We only present these templates to provide a reference between the data files and the respective templates SINFONL ifs cal Arcs Internal wavelength calibration Parameters to be specified Parameter Range Default P2PP Label DET DIT 0 3600 NODEFAULT Integration time DIT DET NDIT isf NODEFAULT Number of Integrations NDIT SEQ NEXPO 1 1000 1 Number of exposures per offset position SEQ SPECDITH TF F Spectral dithering INS LAMP1 ST TF NODEFAULT Xenon lamp status INS LAMP2 ST TF NODEFAULT Krypton lamp status INS LAMP3 ST TF NODEFAULT Neon lamp status INS LAMP4 ST TF NODEFAULT Argon lamp status INS OPTILNAME isf NODEFAULT SPAXEL size arcsec INS SETUP NAME i
2. SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 Issue Rev Date Sect Paragr affected Reason Initiation Documents Remarks Issue 84 Issue 87 Issue 88 Issue 89 Issue 90 Issue 93 Issue 93 1 Issue 93 2 2010 01 20 2010 12 21 2011 03 01 2011 08 26 2012 05 24 2013 09 01 2013 09 27 2013 12 09 1 12 2 2 entire doc 12 12 3 4 none 2 6 none All All All Update of the introduction section clarification additional explanations of the SINFONI offset convention general update of the entire document Update for P87 Phase 2 a new tem plate SINFONI ifs cal GenericOffset is available to allow efficient PSF obser vations in LGS noTTS mode Seeing Enhancer mode To be used for P88 no changes w r t P87 Phase 2 To be used for P89 details on detector persistence added To be used for P90 no changes w r t P89 To be used for P93 New section on pupil tracking mode added In formation in many sections are up dated revised To be used for P93 New figure on in strument orientation Expanded infor mation on Pupil Tracking mode Gen eral tidying up To be used for P93 phase 2 More infor mation on Pupil Tracking mode Many sections are updated SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 iv SINFONI in a Nutshell SINFONI is a near infrared 1 1 2 45 jum integral field spectrograph
3. Organisation Europ ene pour des Recherches Astronomiques dans l H misph re Austral Europ ische Organisation f r astronomische Forschung in der s dlichen Hemisphare ES EUROPEAN SOUTHERN OBSERVATORY o A ESO European Southern Observatory Karl Schwarzschild Str 2 D 85748 Garching bei M nchen Very Large Telescope SINFONI User Manual VLT MAN ESO 14700 3517 Version 93 2 Date 2013 12 09 Prepared LUC EE EE et du Date Signature Approved Ar K ufer A eee ee a Date Signature Released C Dumas 08 haf cack cache edicts ienladasigsde cede hs Wiad a Date Signature VLT Paranal Observatory x Telephone 56 55 435000 x Fax 56 55 435001 SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 Change Record Issue Rev Date Sect Paragr affected Reason Initiation Documents Remarks Issue 1 01 09 2004 all First release intended for phase 1 P75 Issue 1 1 21 10 2004 12 Template reference included for SV and GTO runs in Nov 2004 Issue 1 2 05 01 2005 Version prepared for phase 2 of P75 Issue 1 3 24 05 2005 Minor changes for phase 2 of P76 Issue 1 4 12 03 2006 all parts Added information on availability of LGS and RRM modes for P78 Issue 78 1 2006 04 24 cover amp header Issue number aligned with new format requirements for module archivation Issue 78 2 2006 06 07 cover amp templates IP78 phase 2 RRM LGS PRE imaging al
4. Figure 31 Spectral point spread function in the H K band For the three different plate scales for three regions on the detector top to top top to bottom on detector
5. In Service mode AO observations with AO guide stars much fainter than R 14 mag will require excellent observing conditions The feasibility of such a project must be carefully evaluated and the derived observing constraints should be well selected in the proposal as well as in the later phase of observation preparation In Visitor mode the above recommendation for service mode projects is also valid in visitor mode n cases in which there is only a faint AO guide star one would in parallel prepare observations for no AO seeing limited observations These backup projects for periods in which the AO loop cannot be closed on faint target should be authorized well in advance to the observation run unless the science objectives as given in the proposal can be reached with seeing limited observations as well The color of the AO guide star The color of the guide star is important for two reasons e he very broad response curve of the APDs extends from 450nm to 900nm with the peak SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 6 response around 650nm Thus the R band magnitude provides only a crude estimate of the number of photons detected by the Wave Front Sensor WFS For M stars and later spectral types as well as for other very red objects B R gt 2 2 there will be less light detected by the APDs than for a guide star with a flat spectrum of the same magnitude e The color is also essential for atmospheric refractio
6. Furthermore the approximate size of the AO guide star 0 for point sources only specify the size if you expect it to contribute significantly with respect to the seeing and the approximate magnitude and color of the AO guide star have to be selected These parameters are required to properly set up the AO system with respect to aperture size of the WFS and differential atmospheric refraction between the visual light WFS and the IR spectrograph SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 62 As noted in 812 1 it is important to consider the proper motion of the NGS especially for faint targets since the NGS is also used for blind offset to the target therefore the entered coordinates must be corrected for proper motion for the expected date of observation there is currently no easy way to enter the proper motions of the NGS into the acquisition template Pupil Tracking For pupil tacking mode set PUPILTRK to T The instrument will first rotate to the specified position angle on sky set by TEL ROT OFFANGLE and then the rotator will stop to allow the PA to vary with time The instrument continues in pupil tracking mode until another acquisition template is executed setting PUPILTRK to F The PUPILTRK keyword can be used to change between pupil tracking and field tracking modes even when PRESET F In pupil tracking mode the DPR TECH keyword will be set to IFU NODDING PT and the data can be identified by the TEL ROT ALTAZT
7. The most promising way to overcome the isoplanatic angle limitation is to use artificial reference stars or laser guide stars LGS Laser Guide Stars are artificial sources potentially replacing Natural Guide Stars NGS as reference objects for Adaptive Optics AO image corrections The rationale is the much higher sky coverage offered in principle by an LGS as opposed to the standard NGS approach Due to the bright m 12 13 artificial star created near the centre of the field the probability to achieve a given minimum AO correction on an arbitrary astronomical target goes from a mea ger 3 with an NGS to 65 with an LGS with a K band Strehl ratio currently in the 10 20 range Nevertheless there are still a number of physical limitations with a LGS The first problem is the focus anisoplanatism also called the Cone Effect Because the artificial star is created at a relatively low altitude light collected by the telescope forms a conical beam which does not cross exactly the same turbulence layer areas as the light coming from the distant astronomical source This leads to a phase estimation error The effect is roughly equivalent to the phase error experienced with a NGS that is 10 away from the astronomical target Contrary to the case of NGS only AO LGS based corrections are expected to be lower due to the cone effect Even more severe is the image motion or tilt determination problem Because the paths of the light rays are the
8. OH lines for each spectral band and pre optics These frames are used for wavelength calibration The sky frames containing OH lines can be used for a more precise wavelength calibration Arc lamp frames with an ad hoc DPR keyword WAVE TECH are also taken together with fiber frames as part of the north south test to compute the detector s distortion Sky Frames A sky frame must be subtracted from the object frames since the nightsky emission lines are very bright and vary both spatially and in time in the near infrared The sky frame obtained closest in time and distance form the science field must be used otherwise OH line remnants will appear in the final data cube For this reason the sky frames must be included in the template definition Sky frames are produced by templates SINFONI ifs obs FixedSkyOffset SINFONI ifs obs GenericOffset SINFONIL ifs cal StandardStar and SINFONIL ifs cal PSF Standard star Frames Produced by SINFONI ifs cal StandardStar Standard star frames are used to flux calibrate the object frames and to remove the atmospheric transmission features In some cases they can also be used as PSF standards PSF standard Frames Produced by SINFONI ifs cal PSF PSF standard frames are used to generate PSF images They can also be used for flux calibration and as telluric standards similar to standard star frames When operating the pipeline in fully automatic mode the PSF standard frames are reduced i
9. Parameter Range Default P2PP Label TEL TARG ALPHA NODEFAULT RA TEL TARG DELTA NODEFAULT DEC TEL TARG EQUINOX 2000 Equinox DET DIT isf NODEFAULT Integration time DIT DET NDIT isf NODEFAULT Number of Integrations NDIT SEQ NGS DIT isf NODEFAULT NGS integration time DIT SEQ NGS ISTARGET TF NODEFAULT Target AO Guide Star SEQ NGS ALPHA NODEFAULT RA of AO Guide Star SEQ NGS DELTA NODEFAULT DEC of AO Guide Star SEQ NGS MAG 2 25 12 R mag of AO Guide Star SEQ NGS COLOR 1 5 NODEFAULT NGS B R color SEQ NGS FWHM 0 10 0 0 FWHM of AO Guide Star arcsec SEQ PUPILTRK TF F Enable this for pupil tracking TEL ROT OFFANGLE 235 235 0 0 Position angle on the sky TEL TARG ADDVELALPHA 15 15 0 0 Differential tracking in RA TEL TARG ADDVELDELTA 15 15 0 0 Differential tracking in DEC TEL AG GUIDESTAR NONE SETUP CATALOGUE Telescope guide star selection FILE CATA LOGUE TEL GS1 ALPHA 0 0 RA of telescope guide star TEL GS1 DELTA 0 0 DEC of telescope guide star TEL SKY OFFALPHA 120 120 0 0 Telescope offset RA to sky TEL SKY OFFDELTA 120 120 30 0 Telescope offset DEC to sky INS MIRR1 NAME isf Ref SkySpider Position INS OPTI1 NAME isf NODEFAULT SPAXEL size arcsec INS SETUP NAME isf NODEFAULT Instrument setup name Hidden parameters SEQ NGS NDIT isf 1 NGS number of Integrations NDIT SEQ NGS ACQSAFE TF T Perform slower safe acquisition SEQ NGS SKYALPHA 60 60 4 0 WFS Alpha sky offset arcsec SEQ NGS SKYDELTA 60 60 4 0 WFS Delta sky offset arcs
10. This leads to random phase delays that corrugate the wavefront WF The path differences are to a good approximation achromatic Only the phase of the WF is chromatic The correlation time of WF distortions is related to the average wind speed V in the atmosphere and is typically of the order of ro V 60ms at 2 2 um and V 10m s 7 1 2 Adaptive Optics A powerful technique in overcoming the degrading effects of atmospheric turbulence is real time compensation of the deformation of the WF by adaptive optics AO Figure 8 The wavefront sensor WFS measures WF distortions and these measurements are processed by a real time computer RTC The RTC controls a deformable mirror DM which compensates the WF distortions The DM is a continuous thin plate mirror mounted on a set of piezoelectric actuators that push and pull on the back of the mirror Because of the significant reduction in the WF distortions by continuous AO correction it is possible to record near diffraction limited images with exposure times that are significantly longer than the turbulence correlation time The residual error from the WF compensation WF error directly determines the quality of the formed image One of the main parameters characterizing this image quality is the Strehl ratio SR which corresponds to the amount of light contained in the diffraction limited core relative to the total flux An AO system is a servo loop system working in closed loop The DM flatt
11. distortion coefficients should be constant Slitlet Distances A fits table describing the distances from one slitlet edge to another Pixel distances of the slitlets depend on which spectral band is used These distances are used in cube reconstruction Slitlet distances should remain constant unless the instrumental setup is changed Master Flat Field Master flat fields are obtained by stacking on off flat field frames There is one master flat field for each band and preoptics Master flat fields should be generated each day Master Darks Master darks are obtained by averaging dark frames with the same DIT A master dark frame should be generated for each DIT used Slitlet edge position Positions of the slitlet edges for each spectral band and pre optics These positions can be deter mined from a spectral arc lamp frame Slitlet edge positions are used for bad pixel interpolation Wave Map Wavelength calibration solution for each band and preoptics 6 2 Data Reduction Steps In this subsection methods used by the pipeline to generate calibration and science products are briefly described 6 2 1 Detector Linearity and Bad Pixel Mask Determination Recipe sinfo_rec_detlin Purpose Bad non linear pixels determination Linearity flat fields are sorted in a stack according to the intensity and on each pixel intensity variation through the stack is fit with a polynomial A clean mean of the polynomials is computed and pixel
12. pressure difference between the two dichroic surfaces bends the dichroic and induces a small 20nm rms wavefront error on the reflected wavefront mainly astigmatism The image motion on the CWFS caused by outside pressure variations is negligible lt 1mas hr Cassegrain M4 Figure 12 Main optics 8 1 3 The Corrective Optics The wavefront correction is performed by a 60 electrodes bimorph mirror developed by CILAS with a pupil diameter of 60mm The 60 electrodes are gold printed and sandwiched between two 0 8mm thick PZT layers with opposite polarisation The outside surface of the PZT layers are grounded and covered with a 0 1mm glass layer aluminium coated Applying a voltage to one electrode produces a constant curvature over its surface of 5km for 1V The geometry of the electrodes in the 4 central rings 40 electrodes matches that of the lenslet array sub apertures The 20 remaining electrodes are deposited outside the pupil and are used to constrain the edge of the pupil correction of curvature free aberrations tip tilt astigmatism SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 42 The DM provides correction to compensate all atmospheric aberrations up to a seeing of 1 arcsec measured at 500nm In addition the incoming wavefront is also affected by a slower tip tilt error mainly induced by the telescope which amplitude exceeds the correcting capability of the DM To provide this additional stro
13. telescope background The total instrument telescope background was measured in the 250 mas plate scale as flux per pixel 250 mas x 125 mas for the two cases no OH avoidance e averaging over the full spectral range and with OH avoidance i e avoiding the brightest OH lines Band incl OH between OH J 0 14 0 07 e s H 1 26 0 11 e s K 3 64 0 90 e s H K 5 96 0 80 e s This converts to the following magnitude per square arcseconds Band incl OH between OH 1 15 9 16 7 mag H 13 9 16 5 mag K 12 6 14 2 mag H K 13 2 15 3 mag SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 9 slitlet ba Fit exponential decay D slitlet SINFONI Persistence Decay ratio of 2 5 T pe slitlet ratios ratio 0 957 470 506 mid 55641 639 nominal level 2 0 1 0 17 Gr 10 Ratio of Raw Dark Slitlets 0 5 A i ns Marr EE NN NER 0 0 Ll d 05 n gt gt o gt gt ry EK 6 E 9 6 f f d f gt gt gt P BU S Date created 2011 03 29 18 29 16 m neeser Figure 2 Decay of persistence artefacts after a worst case saturation event demonstrating that such artefacts can last up to several days and severely affect subsequent observations both science and calibrations In the shown example the persistence was revealed and traced through the flux ratio of slitlets 17 and 32 in dark exposures of DIT 6005 2 8 Recom
14. 80 km Detailed sky spectra with OH line SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 37 identifications are available on the ISAAC web page Beyond 2 2 um the thermal background dominates The thermal background consists of atmospheric and telescope emission 7 3 3 Spectrophotometric Calibration Calibration of spectroscopic data in the IR is a complicated procedure that requires care It is generally done in three steps The first step removes telluric features with what is commonly called a telluric standard the second step removes the spectral features of the telluric standard that are imprinted onto the science spectrum because of the first step and the third step sets the absolute scale with what one may call a spectroscopic flux standard In general the spectroscopic standard and the telluric standard are the same star but this does not need to be the case The most prominent features in IR spectra are the telluric lines of the Earth s Atmosphere Unfor tunately many of the telluric lines do not scale linearly with airmass so it is necessary to observe a standard at the same airmass and with the same instrument setup as that used for of the science target Furthermore the strength of the telluric lines varies with time so it is also necessary to observe the standard soon after or soon before the science target The spectrum of the telluric standard is divided directly into that of the science target Ideally t
15. Furthermore for LGS observations the RTC does not give a true representation of the real Strehl ratio For faint object observations if you wish to estimate the Strehl PSF of the AO Guide Star use the template cal NGS to record an image Reference PSF stars can also be obtained by preparing a dedicated OB using the SINFONI ifs cal PSF template Note that for AO observations the PSF will be under sampled for the 250 and 100 mas scales and it is not possible to measure the Strehl accurately from the images SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 26 5 7 Orientation convention Fig 7 shows the orientation convention used for SINFONI The Position Angle on sky of the instrument as specified in the acquisition template corresponds to the angle of the y axis of the instrument FOV makes on the sky measured Eastwards from North See also 12 1 for more details and examples PA 0deg PA 45deg Figure 7 Illustration of the orientation convention for SINFONI for a Position Angle on sky of 0 deg left and 45 deg right 5 8 Offset conventions and definitions For a position angle of 0 the FOV corresponds to North up and East left The position angle is defined as the angle the Y axis of the FOV makes relative to the North measured eastwards from North SINFONI follows the standard VLT offset conventions and definitions All offsets are given in arc seconds but the reference system can be chosen to be t
16. L a dall Vai ree ul ul m CI 8 R 55558 5 E E B E B amp 852 EE A LAN UGH Qi iaa AG LLL LLLI e PTTL TET TLE 8p S S S 3 S S occa 14 T ees T 14 T loot 0003 onne looo Ll orz gor mots tts vote OLOLZ SISET sran 02861 SEBET 06861 92861 02861 T T T maer I SEBET 08861 92861 T T T maer I S 3 S 3 8 d ar 244 T S97 44 T T T OA A PUTT TTT TTY A Mm Ln C 3 E TS ps om B So E Ss E E 4S CH az O e e Lei Ce Mm Ln z 73 Figure 30 Spectral point spread function in the K band For the three different plate scales for three regions on the detector top to top top to bottom on detector SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 81 EEE 8 883888 H WW Majin TTT TTTT TTTTITTTTTTTTTTTTE eh IST RTL i p SH SE 8 8 He E SL A E sL a i x 5 SL g 8 B R Lo wluduuuduuluul A Olli AAPA OTA ARTY OTTO T lla g SS 8 8 8383888 e PETTA E ETERA ADA A O LL al i f E NE E Tar T A l E Z s d rn Y EL 13 E 8 8 c A 8 SL S E Se v 5 ar an d O S J E UJ sr at H Es vull vluluuludhuulu oad GOW FERI EETA O n E R DEL EEE LEER TUIOU DIET An AE E E E 13 8 8 He j a E E E i E sl SS E El D ld vull Jul
17. NGS take the exposure and the sky frame and setup the field selector mirror back to the science target The template can be attached to any science exposure which is taken in closed loop In the case of LGS observations We recommend the user to insert this template before the science template particularly if the science target is not visible and the NGS Tip Tilt Star im age is used to recenter image cubes obtained at different dates The LGS observations are more sensitive than NGS observations to changes in the meteo conditions As a result the AO loop SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 73 has a higher probability to crash during long science target observation sequences if the conditions deteriorate Obtaining the Tip Tilt Star image before starting the science template secures the reference position to be obtained even in case the science template is later aborted Please find the explanation of the parameters within the description of the GenericOffset template SINFONL ifs cal NGS PSF calibration star observation Parameters to be specified Parameter Range Default P2PP Label DET DIT 0 3600 NODEFAULT Integration time DIT DET NDIT LIST isf 11 List of number of integrations NDIT SEQ NOFF 1 100 2 Number of offset positions SEQ OBSTYPE LIST OS NODEFAULT List of observation types O or S SEQ OFFSET COORDS SKY DETEC SKY Offset coordinate type selection TOR
18. RACK keyword T if pupil tracking 12 1 2 SINFONI ifs acq NGSfast The NGSfast acquisition template will preset the telescope and setup the instrument to the final instrument scale and spectral range In a first step the NGS will be centered in open loop using directly the final scale The second step repeats the acquisition in closed loop Finally the science target if different from NGS can be centered if it is visible in the user selected exposure time For most fields the coordinates of the UCAC2 catalog should be accurate enough The coordinates of the science target and NGS should be also known in the absolute celestial coordinate system in case of a telescope guide star selected from UCAC2 Because i this template is reserved for very bright NGS which would cause persistence on the detector if the normal acquisition template is used and ii there is a risk of not seeing the target in the small field of view of SINFONI if the coordinates are not known with sufficient accuracy a waiver submission is required to use this acquisition template in service mode Pupil tracking is also available for this mode see the description in INFONL ifs acq NGS above This template should be used for bright targets to avoid causing persistence problems on the detector SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 63 SINFONI_ifs_acq _NGSfast Fast Natural Guide Star Acquisition Parameters to be specified
19. This figure is meant to illustrate where on the detector the image of a point source is showing up if the telescope Is doing the offset sequence as specified for the parameters List of offsets in RA or X and List of offsets in DEC or Y in the above table and if the source is centered on the detector at the start of the template 12 2 3 SINFONIL ifs obs AutoJitter The template offsets the telescope between the exposures jitter according to a random pattern automatically determined by the template It should be only used in the widest field of view of SINFONI It is only offered on best effort basis since it is well known that even with the AO system the wings of the PSF which contain at least 4096 of the light will be distributed to about the seeing limited PSF It is the user s responsibility to ensure that the sky subtraction is not compromised The jitter offsets are distributed within a box whose size is defined by the parameter Jitter Box Width in arcseconds with the condition that the distance between any two points in a series of ten frames is greater than a certain minimum This is intentionally done to ensure that the 5 frames before and after any frame are spatially not too close to each other for the sky subtraction Defining too small jitter box widths full size of the box will make a proper sky subtraction difficult if not impossible Too large boxes will lead to a poor image overlap There is no offset executed before taking
20. although mainly to observe telluric standards of known JHK magnitudes to allow the removal of telluric features and to derive an estimate of the instrument response function for the flux calibration of the science data This template would be typically used by the observatory staff spart of the calibration plan unless there is a special request for a user selected standard In that case the user has to supply his her own standard using this template The PSF template is available to obtain an estimate of the instrument PSF by observing a user selected typically bright PSF reference star The StandardStar and PSF templates are identical to the GenericOffset template in keyword content and function There is furthermore a NGS template offered which will center the natural guide star NGS to the center of the image slicer to estimate the PSF by on axis observations of the NGS The parameters to be set in the template are DIT NDIT and the value of the fixed sky offset The template is only useful if target and NGS are not identical Attached lamp calibrations are also provided These templates will read the exposure times and lamp setups from a local data base Accordingly there is only one parameter left over the spectral dither flag which defines whether spectrally dithered calibration should be taken or not 12 3 1 SINFONI_ifs_cal_StandardStar As mentioned above this template is almost exclusively used by the staff to take telluric and f
21. bright K lt 6 mag targets 12 1 Acquisition Templates Unlike for other instruments there is no imaging mode available All data is taken in the format of an integral field spectrograph the slices sorted in x direction and the light dispersed in y direction on the detector Interactive acquisition procedures are done on the reconstructed images These images are calculated within seconds in real time on the instrument control workstations There are three acquisition templates offered for SINFONI The very interactive SINFONI_ifs_acq_NGS will center the natural guide star NGS first in open and then in closed loop in the field of view of the widest 250mas scale SPAXEL size Then a final centering of the NGS and the target will be done on the user selected scale In case of the SINFONI_ifs_acq_NGSfast template the interactive steps on the wide 250mas scale are skipped to allow the acquisition of bright NGS K lt 6 mag without saturating the detector array The centering of the NGS is done on the smaller user defined scale Accordingly the coordinates of the NGS and the target must be more accurately known then for the normal target acquisition procedure The SINFONI ifs acq noAO template will interactively center the target or a reference star in blind end offset mode in noAO open loop mode The main function of the acquisition template is to preset the telescope to setup the instrument and to move the target to the center of the
22. by default during the acquisition unlike for NACO for example Telluric standard stars of early types B1 to B9 are part of the calibration plan for science ob servations See 11 for details If you need a telluric of a particular spectral type please give instructions in the README and this will be done on a best effort basis PSF standard stars are not part of the calibration plan If you wish to observe a PSF standard star please prepare an OB with the template _cal_PSF Alignment of images from different nights faint targets noAO only For the closed loop AO observation the position of the field selector mirror can be used to align images taken in different nights For open loop noAO observations of faint targets acquired with blind offsets it is recommended to add the template SINFONI_ifs_cal_PSF with the blind offset swapped in sign to take an image of the blind offset star 4 2 2 Observing Blocks OBs Any SINFONI science OB should contain one acquisition template followed by a small number of science and optionally night time calibration templates There are only three calibration templates which may be attached to night time science SINFONI OBs e The special nighttime calibrations cal ArcsAtt and cal LampFlatsAtt that may only be attached at the end of the OB OBs which include night time calibrations must contain only one instrument set up J H K or H K and the attached calibration templates at the end
23. ee 15 13 The Spectral Resolution of SINFONI TT SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 1 1 Introduction 1 1 Scope of this document The SINFONI User Manual provides comprehensive information about the technical characteristics of the instrument the observations procedures and the reduction of SINFONI data The actual version was updated with the latest information about the detector and observing modes offered We welcome any comments and suggestions which should be addressed to our User Support De partment usd helpOeso org In addition to this User Manual complementary information about SINFONI is also provided on the SINFONI webpage http www eso org sci facilities paranal instruments sinfoni which you are invited to visit regularly for any last minute update 1 2 Structure of this document The document is structured in 3 parts Part 1 I takes you step by step through the essentials writing your proposal in phase 1 preparing your observations in phase 2 conducting your obser vations at the telescope and reducing your data If you want to learn more about the instrument itself you might want to read through Part 2 II Finally Part 3 Ill contains the SINFONI calibration plan a description of the templates and collected useful reference material 1 3 Latest changes From P93 onwards SINFONI will be offering a new Pupil Tracking mode allowing medium con trast imaging spectroscopy
24. frames are combined to determine a master flat and undistorted WAVE_LAMP frames are used to determine a wavecal solution Then distortions are determined on the fake on off frame Finally the fake on off frame is distorted and the slitlet distances are determined with a north south test Purpose 2 calculating slitlet distances Each of the 32 continuum slit spectra are fitted by a Gaussian along spatial direction at each row This determines the position of the slitlets for each row These positions are averaged for each slitlet and the distance of each slitlet from the reference is computed 6 2 5 Wavelength solution determination Recipe sinfo_rec_wavecal Purpose generates a wavelength calibration map Clean mean is computed for both on and off frames and off frame is subtracted from on frame The resulting frame is flatfielded corrected for bad pixels and distortion and convolved with a gaussian Emission lines are searched by crosscorrelating with synthetic spectrum created from reference line table and approximate dispersion relation Emission lines at each image column are fitted and the found lines are stored in an output file At each column a polynomial fit is carried out on the found emission lines Within each slitlet polynomial parameters are smoothed and stored in an output file These smoothed polynomial parameters are used to generate a wavelength calibration map SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3
25. number of DITs to be integrated before writing the data to disk Number of AB or BA cycles defines how often the AB cycle is repeated Set to one the template will take a AB sequence set to two it will take a ABBA sequence object sky sky object with three a ABBAAB sequence For best sky subtraction the parameter should be set to values of three or larger Number of offset positions defines the number of offset positions in case of the GenericOffset and AutoJitter templates SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 66 Number of exposures per offset can be set to values different from 1 in cases where more than one jittered exposure shall be taken at a given on off position before nodding to the next on off position For typical applications it should be 1 for all templates with ABBA sequences nodding between object and sky positions SPAXEL size and Instrument setup name define the SINFONI instrument setup The Spaxel size is the size of the image slice 0 025 0 1 and 0 25 arcsecs on the sky The Spaxel is projected to 2 pixels by the SINFONI collimator and camera optics The instrument setup name is a symbolic name for the setup required to center the J H K and H K spectra on the detector The respective setups transparent to the user include the selection of the grating grating angle spectral order and order sorting filters The SkySpider Position should be left in the ref erence position si
26. of the OB e And _acq_NGS to be attached typically right after the acquisition template in order to record an image of the AO Natural Guide Star For the large majority of projects the night time observation blocks will contain only one science template and the mandatory target acquisition template 4 2 3 P2PP Using P2PP see http www eso org sci observing phase2 P2PP P2PPTool htm1 to pre pare SINFONI observations does not require any special extra programs no file has to be attached except for the finding chart 4 3 Finding Charts README Files and OB Naming Conventions In addition to the general instructions on Finding Charts and README files that are available at http www eso org sci observing phase2 P2PP P2PPTool html the following applies for SINFONI SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 22 e The field of view of all finding charts should be U by 1 in size with a clear indication of field orientation e Ideally the finding chart should show the field in the NIR or at least in the red and the wavelength of the image should be specified in the FC or the README file e The AO guide star if used should be clearly marked e The bright star from which to offset if used should be clearly marked e The 8 x8 field of view as well as the final field of view should be marked in their correct orientations e The OB names for PSF calibration stars should be prefixed with the strin
27. offsets between the images taken at the selected object and sky positions The recommended template FixedSkyOffset will automatically take exposures in an ABBA sequence with the respective A object and B sky positions randomly jittered with respect to each other The GenericOffset template allows to specify any sequence of object and sky positions The AutoJitter and AutoJitterSpider templates are not nodding between object and sky position In case of the AutoJitterSpider the sky is taken with a periscope which can be deployed in front of the image slicer into the field of view of the spectrograph The systematics of this mode is however not yet studied and explored well enough to be supported The AutoJitter template may be used with large jitter box widths 4 to 7 on the widest 250mas SPAXEL scale with a field of view of 8 The offsets calculated by the software are in units of full pixels 12 5 50 125mas The jitter offset improves therefore the spatial sampling in y direction by offsetting in steps of half of the image slice Note All science templates have the hidden parameter Return to Origin set to True which means that at the end of the template the science target returns always to its original position regardless of the offset sequence used during the template execution The common parameters to these templates are described here DIT and NDIT are the user defined integration time for the exposures of the target and the
28. same on the way up as on the way down the centroid of the artificial light spot appears to be stationary in the sky while the apparent position of an astronomical source suffers lateral motions also known as tip tilt The simplest solution is to supplement the AO system using the LGS with a Tip Tilt Star TTS which can be chosen much fainter than an AO star Performance is then limited by the poor photon statistics for correcting the tip tilt error The need of a nat ural guide star for tip tilt sensing is the reason why sky coverage cannot go up to 100 for LGS AO Note that starting from P82 the LGS system can also be used without TTS i e seeing enhancer mode no tip tilt correction A moderate improvement in image quality wrt the no AO mode can be achieved under good conditions 7 2 2 LGS mode at Paranal UT4 The LGS focuses at 90 km altitude in the mesosphere exciting sodium atoms at 589 nm The thin layer of atomic sodium present at that height produces an V 11 artificial star to guide the AO servo loop This artificial reference star can be created as close to the astronomical target as desired and the MACAO visible wavefront sensor is used to correct the high order wavefront aberrations on the target object The laser is hosted in a dedicated laboratory under the Nasmyth platform of UT4 A custom made single mode fibre carries the laser light to the 50cm launch telescope situated on top of the secondary mirror assembly providing
29. star in modes other than LGS noT TS mode Seeing Enhancer mode SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 74 SINFONI_ifs_cal_GenericOffset PSF calibration star observation in LGS noTTS mode only Parameters to be specified Parameter Range Default P2PP Label DET DIT 0 3600 NODEFAULT Integration time DIT DET NDIT LIST isf NODEFAULT List of number of integrations NDIT SEQ NOFF 1 100 NODEFAULT Number of offset position SEQ OBSTYPE LIST OS NODEFAULT List of observation types O or S SEQ OFFSET COORDS SKY DETEC SKY Offset coordinate type selection TOR SEQ OFFSET1 LIST NODEFAULT List of offsets in RA or X SEQ OFFSET2 LIST NODEFAULT List of offsets in DEC or Y SEQ SPECDITH TF F Spectral dithering INS OPTI1 NAME isf NODEFAULT SPAXEL size arcsec INS SETUP NAME isf NODEFAULT Instrument setup name Hidden parameters SEQ NEXPO 1 1000 1 Number of exposures per offset position SEQ RETURN TF T Return to Origin T F DPR CATG CALIB CALIB Data product category DPR TECH IFU NODDING IFU NODDING Data product technique DPR TYPE PSF PSF Data product type CALIBRATOR CALIBRATOR 12 3 5 SINFONL ifs cal ArcsAtt This template takes an arc line calibration with whatever setup was selected for the template executed immediately before All parameters are read from our local data base except of the spectral dithering flag There are two exposures taken 4 with spectral dither one with
30. the best possible artificial source image quality As a safety measure a twin whole sky camera with specialized software is used to monitor incoming aircraft and shut down the beam accordingly SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 36 The original laser system PARSEC was based on a 4W CW Sodium Laser 589 nm After six years of service during which it enabled many important discoveries it was decommissioned in the beginning of 2013 Starting from Period 91 a new solid state laser system PARLA has replaced PARSEC PARLA forms a part of the Laser Guide Star Facility LGSF With an on sky power of 7W it is available on most nights greatly improving the reliability and flexibility in operating the LGSF 7 3 Observing in the Near Infrared 7 3 1 Atmospheric Transmission The transmission of the Earth s atmosphere in the J H and K bands is shown in Fig 9 the amount of telluric absorption varies with zenith distance and the amount of precipitable water vapour m TT i 1 1 1 1 20000 21000 22000 23000 24000 Wavelength angstroms Figure 9 Atmospheric transmission in the J H and K bands These graphs are based on FTS data from Kitt Peak produced by NSF NOAO 7 3 2 Background Emission There are two regimes in the sky background emission Below 2 2 jum the sky emission is dom inated by OH emission taking place at an altitude of
31. the wave front sensor which normally is near the centre of the 8 x8 FOV interactively using the reconstructed image Close the AO loop e f the final scale is different than the 250mas scale change to final plate scale interactively re centering the NGS e f the target is not the NGS offset the telescope back to the target If the target is visible in a final short exposure recenter the target For the NGSfast acquisition template the difference is that the 25 mas scale 0 8 x0 8 FOV is used right from the beginning This should only be used for bright stars where there is a realistic possibility of finding the star even if it falls slightly outside the FOV This template is mandatory SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 25 for very bright stars with K lt 6 mag to avoid causing persistence problems on the detector during the acquisition Pupil tracking mode acquisition follows the same procedures as for normal NGS or NGSfast acqui sitions except that after the instrument orientation is set to position angle on the sky specified in the template the rotator is stopped such that the field starts to rotate around the instrument axis The telescope instrument will remain in pupil tracking mode until anther acquisition tem plate is executed with PUPILTRK set to false or when the operator turns it off manually using the instrument panel The acquisition in AO LGS is very similar to the acquisition in AO N
32. the wavefront sensor whose response curve ranges from 450nm to 900nm and peaks around 650nm e Sky conditions and instrument set up should be trivial if no AO guide star is available reset the AO box Note that the seeing constraint in the proposal is at the observed wavelength for seeing limited observations while the input to the ETC is always at V band e Results can be given as exposure time to achieve a given S N or as S N achieved in a given exposure time In both cases you are requested to enter a typical integration time DIT and the S N or the number of multiple reads NDIT The screen output from the ETC will include the input parameters together with the calculated performance estimates Here some additional notes about the ETC output values e The integration time is given on source depending on your technique to obtain sky mea surements and accounting for overheads the total observing time will be much larger e The S N is given per spectral pixel not per resolution element i e to compute your S N for a resolution element make sure that you sum the right number of pixels typically 2 in K and H K bands 3 in H band 4 in J band e Please respect the constraints for not causing persistence effects 2 6 Note also that the levels for persistence avoidance are much lower than the saturation limit Most of the other ETC parameters should be self explanatory and well explained in the online help of the ETC 3 3 Pr
33. type of clouds SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 7 Starting officially with P84 SINFONI also offers a new LGS mode not requiring the use of a TTS no tip tilt correction the so called Seeing Enhancer SE mode Nevertheless in addition to specifying CLR or better for the sky transparency users requesting the SE mode must specify a seeing better than 0 8 in their phase application For highly challenging LGS observations e g faint TTS and or large TTS distances you should consider using the SE mode instead of the full LGS mode To improve the chances of your OB being successfully executed you may also want to specify in the README in your Phase 2 materials to ask to automatically fall back to SE mode if a full LGS mode fails 2 3 Spectrograph modes Field of view The pre optics of the spectrograph allow to chose between 3 plate scales providing fields of 8 x8 3 x3 0 8 x0 8 Each of these fields is then cut into 32 slices and each slice is projected onto 64 detector pixels Thus the spatial resolution elements spaxels on the sky are rectangular Field of view Spaxel size on the sky 8 x8 125mas x 250mas 3 x3 50masx100mas 0 8 x0 8 12 5masx25mas Wavelength bands Four gratings are installed on a turret in the spectrograph J H K H K The dispersions are chosen such that the full wavelength range is covered by the detector in each case Band Dispersion F
34. wavelength bands with respect to the K band on axis data distance K 2 25u4m H K 1 95um H 1 65um J 1 25um 0 1 00 0 83 0 63 0 31 b 0 91 0 73 0 52 0 25 10 0 77 0 60 0 39 0 17 15 0 54 0 38 0 23 0 08 20 0 41 0 27 0 15 0 04 25 0 27 0 17 0 08 0 03 30 0 21 0 13 0 06 0 02 8 2 2 LGS performances The Strehl performance achieved in LGS mode has been evaluated for on axis observations by combining e the performance estimation obtained for the NGS mode with a guide star brightness corre sponding to the expected LGS brightness and e the estimated degradation factors for LGS operations cone effect trombone control error LGS jitter effect of the LGS spot size aberrations introduced by the LGS additional optical elements STRAP performance depending on the pointing star brightness tip tilt anisoplanetism The theoretical Strehl performance in K band is shown in Fig 18 for a 0 65 arcsec seeing at 500 nm The measured Strehl improvements are currently lower in the 10 range under me dian seeing conditions and up to 20 under the best seeing conditions using Tip Tilt stars with R lt 18 mag Please refer to the ETC http www eso org observing etc to estimate system performances for your particular observations SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 48 SINFONI Laser Guide Star Mode Strehl ratio K band D 5 10 15 20 25 30 Pointing star
35. you have previously observed with other NIR in struments at the VLT or NTT They allow variations in the strategy of obtaining sky measurements Things to look out for are e As standard for ESO instruments the offsets are cumulative e The offset convention are different between Detector and Sky e Spectral dithering is not offered nor is the AutojitterSpider template Calibration Darks arc wavelength calibration and lamp flat field exposures are taken during daytime as part of the calibration plan see 8 11 If for a particular reason you wish to obtain arcs or lamps immediately after your exposure you can attach the template cal ArcsAtt or cal LampFlatsAtt at the end of your OB We have found during the commissioning phase that the instrument flexures were small and that night time calibrations are not required Therefore we discourage taking arc or lamp exposures during the night Furthermore instrument flexture can also be corrected for in the spectral direction using the sky emission lines SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 21 If you wish to estimate exactly the image quality obtained on your AO guide star you can insert in your OB the template _cal_NGS immediately after your acquisition This will set back the AO guide star into the spectrograph field of view and obtain an image of the NGS which can later be used for performance PSF analysis Please note that such an image is not taken
36. 0 DEC of telescope guide star TEL SKY OFFALPHA 120 120 0 0 Telescope offset RA to sky TEL SKY OFFDELTA 120 120 30 0 Telescope offset DEC to sky INS MIRR1 NAME isf Ref SkySpider Position INS OPTI1 NAME isf NODEFAULT SPAXEL size arcsec INS SETUP NAME isf NODEFAULT Instrument setup name Hidden parameters SEQ NGS ACQSAFE TF T Perform slower safe acquisition SEQ NGS SKYALPHA 60 60 4 0 WFS Alpha sky offset arcsec SEQ NGS SKYDELTA 60 60 4 0 WFS Delta sky offset arcsec SEQ NGS SNR 0 0 10000 0 1000 0 Minimum S N for AO guide star SEQ NGS USELASTSKY TF T Use for WFS the last measured sky value SEQ PRESET TF T Preset flag DPR CATG ACQUISITION ACQUISITION Data product category DPR TECH IFU IFU Data product technique DPR TYPE OBJECT OBJECT Data product type Warning The full interactive target acquisition with the centering of the NGS on the largest SPAXEL scale would cause saturation and remnance effects on the detector for natural guide stars brighter than 5th magnitude J H K and 6th magnitude H K Any such event would compromise the data quality of the observations and calibrations taken within the next 12 hours It is obvious that any such saturation events must be excluded at any time Please take care NGS parameters The parameters for the AO guide star are a logical flag Science Target AO Guide Star and the coordinates of the AO guide star in RA and DEC with the same Equinox as that specified in the Target section of the OB
37. 1 1 The AO Adapter All the opto mechanical elements described in this section are mounted to a single Aluminium structure the AO adapter which also provides the mechanical interface to the electronic cabinets and to SPIFFI MAIN OPTIC M4 IR DICHROIC Y SPIFFI ENTRANCE WINDOW STRAP FS LENS ND FILTER WHEEL LGS TROMBONE SCANNING LENS IMAGING LENS yok LENSLET ARRAY N MEMBRANE MIRROR CWFS ND FILTER WHEEL WFS OPTICS M1 to M4 Z FDR 4 15 08 2001 Figure 11 Optical layout of the AO module 8 1 2 The Main Optics The optical elements of the AO Module are displayed in Fig 11 The input f 13 4 beam is folded by a first flat mirror M1 and then collimated by an off axis parabola M2 creating an image of the pupil on the Deformable Mirror DM M3 The output SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 41 f 17 1 focus is then created by a second off axis parabola M4 and reflected towards the SPIFFI focus by a second folding mirror M5 Due to tight volume constraint it has not been possi ble to find a solution with only one folding mirror in order to reduce the thermal background contamination of SPIFFI Ahead of the SPIFFI focus an IR Dichroic reflects the visible range 450 950nm towards the wavefront sensor while the IR science band 1 05 2 45 um is transmitted to SPIFFI The dichroic is mounted to SPIFFI and serves also as an entrance window for the cryostat The 750 mbar
38. 100 um core diameter When the membrane mirror vibrates the pupil image is alternatively projected on both sides of the lenslet array plan The normalized difference between the intra and extra pupil flux collected by each sub aperture is proportional to the local curvature of the wavefront which provides the wavefront error signal The 60 fibers drive the signal from the Fiber Feed Module to the APD cabinet mounted to the instrument The APD counts are recorded by the APD counter module synchronously with the membrane drive signal Figure 14 WFS optics Membrane mirror Gimbal mount Lenslet array Fiber module 8 1 5 LGS mode elements The Laser Guide Star Facility LGSF installed on YEPUN VLT UT4 has the following main features e Launch telescope behind VLT M2 e Continuous sodium wave 589nm e Return flux 10 photons sec m at Nasmyth focus goal 1 5 10 for zenith pointing equiv alent to an my 11 FO star seen through the AO Module with APDs e Altitude of LGS 90km 10km e LGS jitter lt 50 mas rms e LGS FWHM lt 1 25 for zenith angle lt 45 deg and seeing lt 0 8 at zenith The LGS provides a good wavefront reference for the observation of high order aberrations but not for the observation of the pointing error since the atmospheric turbulence also affects the upwards SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 44 path of the laser and produces a jitter of the beacon posi
39. 3 Latest changes 2 uu GS RE EEE ESPERE A A co APP 15 Abbreviations and Acronyms 0000 eee ee Observing with SINFONI from phase 1 to data reduction 2 SINFONI Performance overview 2 1 Reference source for wavefront sensing 22 Laser Guide Star LGS observations 2 6 44 44 bos dees owed lens 223 Spectrograph modes cue ss ko ERE RE RR eee eH OS 24 RRM mede aida sario aaa daa xx Wels 25 Prelmaging Mode s A X E oy aras e 304 yo ded ie 2 6 Saturation and persistence limits a 2 7 Total instrument telescope background 2 2 2 8 Recommended DITs and NDITS Object Sky pattern 29 Pupil Tracking Mode o es e bs nde bbe ga ee eee EES bE EEE bale d 2 9 1 Expected performance 4 4454 548 44 48 e844 e482 E 202 Important considerations uu ex mo sl 9e 3 3 Phase 1 applying for observing time with SINFONI 3 1 ls SINFONI the right instrument for your project 0 3 1 1 The AO guide star 1 49 ERG RA RAI RR 3 12 Limiting magnitudes lt 2 gt sac crec RR SR xx merica a 3 2 The Exposure Time Calculator ETC A4 Jee TOR 2o semog eet Ne EE ad 4 Phase 2 Preparing your SINFONI observations 4 1 Do you have all information in hand e 4 2 SINFONI specifics to templates OBS and ppp ooa ONE c MD 4 22 Observing Blocks OBs 02 0000 eee ee ee AR e te e ee a scm aR Aw ERR ER a BR Ra BERS A0 Bod d 4 3 Finding Charts README Files and OB Naming Conventio
40. 517 32 Furthermore it is possible to compute the slitlet positions during wavelength calibration using either a Boltzmann relation or linear slope However this is not as robust a method as obtaining slitlet positions from north south test frames Note 1 a linearly offset map can be created using higher order polynomials from one wavelength map and the Oth order coefficient from another Note 2 wavelength calibration is sensitive to the quality of the bad pixel map If a bad bad pixel map is used it is very likely the recipe will fail 6 2 6 Standard star data reduction Recipe sinfo_rec_jitter Purpose Photometric calibration For each object frame the closest sky in time is selected and the pair is stacked Objnod step is executed on the stacked frames and the resulting wavelength calibrated data cubes are combined Standard star spectrum is optimally extracted from the cube Optionally a mag to counts sec conversion can be determined 6 2 7 PSF data reduction Recipe sinfo_rec_jitter Purpose PSF amp Strehl analysis For each object frame the closest sky in time is selected and the pair is stacked Image reconstruc tion is done by collapsing the image columns The PSF file is generated and Strehl calculated 6 2 8 Science observations Recipe sinfo_rec_jitter Purpose Creating a wavelength calibrated data cube from object sky frames obtained in jittering mode Instrumental signatures are removed For each object f
41. Cassegrain focus the gravity load on the Field Selector is changing with time As a consequence the stiffness and accuracy requirements on the linear translators are very stringent This is also true for the STRAP see below Field Selector SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 43 The imaging lens is creating an image of the guiding star on the membrane mirror which is mounted to an acoustic cavity voice coil is mounted to the other end of the cavity and driven at 2 1kHz by the APD counter module to force an oscillation of the focus mode of the membrane mirror The incidence angle of the beam on the membrane mirror depends on the position of the guiding star in the field In order to keep the pupil image obtained when the membrane mirror is flat centered on the lenslet array the membrane mirror is mounted on a 2 axis gimbal which is co ordinated with the field selector A diaphragm in front of the membrane enables the field to be adjusted to the observing conditions seeing and guiding reference size The wavefront sensor box consists of 4 mirrors which provide a parallel beam to image the pupil on the lenslet array First the beam is collimated by a spherical mirror It is then folded by a flat mirror and injected in the beam expander which adapts its diameter to the lenslet array 14mm The Lenslet Array intercepts the beam and divides the flux in 60 sub aperture Each sub pupil is imaged on a fiber with a
42. DU Dark current at 189 deg C 0 15 e s Noise RON 16 e for short DITs depending on integration time DIT in none destructive readout mode down to 7e at DIT 100s Linear range 1 45000 ADU or 110000 e Saturation level 45000 ADU or 110000 e Note The detector can show a strong persistence effect even after being illuminated below the saturation level typically 10k ADUs This is being investigated Note that if illumination was close or beyond saturation the time scale to recover from the persistence is longer than an observ ing night SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 53 10 Software Overview Figure 23 shows the MACAO Software the external modules with which it interfaces and the overall context in which it operates In normal operation MACAO is used in conjunction with the SPIFFI instrument and is co ordinated by the SINFONI SOS SINFONI Templates SOS GUI MACAO ki SPIFFI RTD ASM MACAO SPIFFI TCS LGSF VOLAC Fast LGSF Uplink T T signal Figure 23 SINFONI software overview The functions of the software entities shown in the diagram are e SINFONI SOS Supervisor Observing Software This module is used to coordinate the activity of MACAO with the other sub systems required to perform a SINFONI observation These sub systems are TCS Telescope C
43. F F Spectral dithering INS OPTI1 NAME isf NODEFAULT SPAXEL size arcsec INS SETUP NAME isf NODEFAULT Instrument setup name Hidden parameters SEQ NEXPO 1 1000 1 Number of exposures per offset position SEQ RETURN TF T Return to Origin T F DPR CATG SCIENCE SCIENCE Data product category DPR TECH IFU NODDING IFU NODDING Data product technique DPR TYPE OBJECT OBJECT Data product type Figure 26 illustrates the execution sequence of the template for a set of parameters which would simulate some sort of a user defined Jitter pattern without nodding to sky positions Typically the users should define also type S sky positions away from the wide seeing limited wing of the PSF which contains at least 40 of the light SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 69 Offset coordinate type DETECTOR SKY Number of offset positions 8 8 List of observation types o o List of offsets in RA or X 010 1 0 0 10 01 4 0 1 4 0 O 1 4 0 List of offsets in DECorY 002 0 2 2 02 0 O 2 8 O 2 8 2 8 O0 2 8 SPAXEL size 0 25 0 25 SINFONI ifs obs GenericOffset SINFONI iif obs GenericOffset Y Y E N Position Angle 45 deg E N Position Angle 45 deg 7 6 gt 4 3 8 5 gt gt e L B lL 2 L 2 4 L L 7 6 W I 1 1 x 11 X Figure 26 An illustration of the offset sequence taken with the GenericOffset template Left side Offset coordinate type DETECTOR Right side Offset coordinate type SKY
44. GS with the following differ ences e After the NGS Tip tilt star is centred on the FOV the laser is first acquired on axis i e centered and focused by the telescope operator The high order also called the pseudo NGS loop and the jitter loops are then closed on the laser e The NGS guide star is centred on the STRAP and becomes the Tip Tilt star which can also be the target The Tip Tilt loop is closed on the star For seeing enhancer mode LGS noTTS the telescope is preset on the final target or on a reference object with a predetermined offset the LGS is acquired and the AO loop closed If the final target is not the same as the reference object the telescope is moved to the target by issuing an offset The acquisition sequence for observation without AO is the following e Preset the telescope to the target coordinates e Flatten the Deformable Mirror using the calibration fiber Offset the telescope to the reference if science target is not visible and interactively center it Change to final plate scale interactively re centering the reference e Offset the telescope back to the target and interactively center it 5 6 Measuring the Strehl ratios reference PSF stars The Strehl ratio is not measured by default during the AO acquisition The real time computer RTC returns an estimation of the Strehl ratio derived from its computations This value is only an estimate and can be off by as much as 20 in some cases
45. IE 4842 375 Figure 21 indicates the positions of the slitlets on a raw SPIFFI frame the slitlets run horizontally across the imaging field of view and are numbered from top to bottom 9 3 Spectrometer collimator After the image has been sliced and re arranged into the pseudo slit three diamond turned mirrors collimate the light onto the gratings The first mirror is spherical and the other two mirrors have Eisenhauer et al 2003 SPIE 4841 p1686 and astro ph 0306191 3Bonnet et al 2004 ESO Messenger 117 p17 SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 50 Image slicer Light entering from the AO module A Spectrometer Detector Figure 19 An inside view of SPIFFI The cryostat cover and the reinforcing structure have been removed to provide a free view on the opto mechanical components of SPIFFI The light enters from the top and passes the sky spider The pre optics with a filter wheel and interchangeable lenses provides three different image scales The image slicer re arranges the two dimensional field into a pseudo long slit which is perpendicular to the base plate Three diamond turned mirrors collimate the light onto the gratings In total four gratings are implemented on the grating drive A multiple lens system then focuses the spectra on a Rockwell HAWAII array The diameter of the instrument is 1 3m an oblate elliptical shape All mirrors are made from Aluminium with a Nickel layer for the diam
46. O system is directly related to the number of lenslets in the lenslet array the number of actuators behind the DM and the rate at which WE errors can be measured processed and corrected the server loop bandwidth The performance of an AO system is also directly linked to the observing conditions The most important parameters are the seeing or more explicitly 79 and V the brightness of the reference source used for WFS and the distance between the reference source and the object of interest In case of good conditions and a bright nearby reference source the correction is good and the resulting point spread function PSF is very close to the diffraction limit A good correction in the K band typically corresponds to a SR larger than 30 At shorter wavelengths particularly in the J band or in the case of poor conditions or a faint distant reference source the correction is only partial the Strehl ratio may only be a few percent SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 35 7 2 The Laser Guide Star mode 7 2 1 Background information on LGS Adaptive Optics operations are strongly affected by the size of the isoplanatic angle usually 20 at Zum but only 5 in diameter at 0 64m However even for observations at 2 2um the sky coverage achievable by this technique equal to the probability of finding a suitable reference star in the isoplanatic patch around the chosen target is only of the order of 0 5 to 1
47. Offset SINFONL ifs cal ArcsAtt SINFONI ifs cal LampFlatsAtt standard star calibration observa tion PSF calibration star observation PSF calibration star observation PSF calibration star observation with user defined offsets to be used in LGS noTTS mode only attached wavelength calibration attached lamp flat calibration calibration plan day time calibration templates SINFONL ifs cal Arcs SINFONL ifs cal LampFlats SINFONL ifs cal Darks internal wavelength calibration lamp flats day time calibration darks calibration calibration plan calibration plan calibration plan Most users can prepare the complete observation runs with the 7 templates which are marked as recommended The calibration templates marked as calibration plan are executed by the ob servatory staff without being specifically requested during the phase 2 observation preparation The observatory will guarantee that these basic calibration observations are taken within the framework of the calibration plan A typical observation block with natural guide star adaptive optics in a normal field would consist of the following templates SINFONI_ifs_acq_NGS SINFONI_ifs_obs_FixedSkyOffset natural guide star acquisition IFS with jitter and nodding to a selected sky field A typical observation block in open loop no AO in a very crowded field would consist of the following templates SINFONI ifs acq noAO SINFONL ifs obs GenericOffset
48. SEQ OFFSET1 LIST NODEFAULT List of offsets in RA or X SEQ OFFSET2 LIST NODEFAULT List of offsets in DEC or Y SEQ SPECDITH TF F Spectral dithering INS OPTI1 NAME isf NODEFAULT SPAXEL size arcsec INS SETUP NAME isf NODEFAULT Instrument setup name Hidden parameters SEQ RETURN T F T Return to origin T F DPR CATG CALIB CALIB Data product category DPR TECH IFU NODDING IFU NODDING Data product technique DPR TYPE PSF PSF Data product type CALIBRATOR CALIBRATOR 12 3 4 SINFONL ifs cal GenericOffset As of P87 Phase2 template SINFONIL ifs cal GenericOffset has been added to allow efficient observations of a PSF calibration star in LGS noTTS mode the PSF calibrations data can be taken within the same OB as the science data Template SINFONI ifs cal GenericOffset can only be used in LGS noTTS mode See ing Enhancer mode as the Tip Tilt loop is always kept open both in Object and Sky positions Hence the template allows user defined offsets to a suitable PSF calibration star beyond the range of the field selector Template SINFONL ifs cal GenericOffset is a clone of template SINFONI ifs obs GenericOffset and its overall functionalities are identical to those of the latter except that all data files are flagged as CALIB Please find the explanation of the parameters within the description of the template SINFONI ifs obs GenericOffset Warning Do not use this template for observations of a PSF calibration
49. SEQ SKY OFFSETDELTA 3600 3600 NODEFAULT Delta offset for Sky SEQ SPECDITH TF F Spectral dithering INS OPTI1 NAME isf NODEFAULT SPAXEL size arcsec INS SETUP NAME isf NODEFAULT Instrument setup name Hidden parameters SEQ POISSON 1 100 10 SEQ RETURN TF T Return to Origin T F DPR CATG SCIENCE SCIENCE Data product category DPR TECH IFU NODDING IFU NODDING Data product technique DPR TYPE OBJECT OBJECT Data product type Figure 25 illustrates the execution sequence of the template for the following set of parameters Number of AB or BA cycles 4 Jitter box width D Alpha offset to sky 20 Delta offset to sky 10 SPAXEL size 0 25 SINFONI ifs obs FixedSkyOffset DEC E Offset Sky Positions Object Positions RA Offset Figure 25 An illustration of the offset sequence taken with the FixedSkyOffset template Number of exposure per Offset 1 The large circles for the sky position indicate that these observations are performed in open loop 12 2 2 SINFONI_ifs_obs_GenericOffset The GenericOffset template has the flexibility to do any sequence of telescope offsets either in detector or sky coordinates The sequence of Object and Sky observations is defined by the SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 68 user The number of integration NDIT per detector readout can be selected differently for object and sky positions The parameter Offset coordinate type select
50. T MAN ESO 14700 3517 1 5 Abbreviations and Acronyms ADI AO APD DM DMD ESO ETC FC FoV FWHM LGS MPE NACO NGS NIR NOVA OB P2PP PSF QC RRM RTC S ADI SINFONI SPAXEL SM SR TIO TTS USG VLT VM WE WES Angular Differential Imaging Adaptive Optics Avalanche Photo Diode Deformable Mirror Data Management Division European Southern Observatory Exposure Time Calculator Finding Chart Field of View Full Width at Half Maximum Laser Guide Star Max Planck Institut fur Extraterrestrische Physik NAOS CONICA or Nasmyth AO System COude Near Infrared CAmera Natural Guide Star Near InfraRed Nederlandse Onderzoekschool Voor Astronomie Observing Block Phase Il Proposal Preparation Point Spread Function Quality Control Rapid Response Mode Real Time Computer Spectroscopic Angular Differential Imaging Spectrograph for INtegral Field Observations in the Near Infrared Spatial resolution Elements on the sky Service Mode Strehl Ratio Telescope and Instrument Operator Tip Tilt Star User Support Group Very Large Telescope Visitor Mode Wave Front Wave Front Sensor 3 Part Observing with SINFONI from phase 1 to data reduction 2 SINFONI Performance overview The following section gives a brief overview of the SINFONI performances We will present more information in Section 8 2 and we refer to the Exposure Time Calculator ETC which should be used to estimate the feasibillity of your scie
51. WHM of line Resolution lambda range J 0 15nm pix Apix 2000 1 10 1 40 um H 020nm pix 3pix 3000 1 45 1 85 um K 025nm pix 2pix 4000 1 95 2 45 um H K 0 50nm pix 2pix 1500 1 45 2 45 um The characterization is complicated by the fact that the spectral PSF is different in each plate scale i e the FWHM of the spectral features i e the spectral resolution varies as a function of plate scale See part II for details 2 4 RRM mode Rapid Response Mode observations with SINFONI are offered since P78 Both NGS and no AO modes are possible although we expect most of the programs will not have a sufficiently bright nearby object to be used as NGS for the AO system If AO can be used in NGS mode please refer to the information available in section 2 1 to understand the limitations imposed by this mode General informations about Paranal s RRM observations are available at http www eso org sci observing phase2 RRMObservation html SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 8 2 5 Pre Imaging mode In case of any uncertainty concerning the feasibility of a program e g source brightness or Strehl achieved for a faint NGS star you can request a pre imaging run to obtain a small subset of data Such dedicated pre imaging run must be explicitly requested in the Phase 1 proposal 2 6 Saturation and persistence limits In open loop noAO observations the target should not be brighter than 5th
52. apability by offsetting from the reference star to the scientific target Pupil tracking is currently not offered for this mode SINFONI isf acq _noAO Open loop acquisition Parameters to be specified Parameter Range Default P2PP Label TEL TARG ALPHA NODEFAULT RA TEL TARG DELTA NODEFAULT DEC TEL TARG EQUINOX 2000 Equinox DET DIT 0 3600 NODEFAULT Integration time DIT DET NDIT isf NODEFAULT Number of Integrations NDIT SEQ FLATTEN TF d Flatten DM using cal unit TEL TARG OFFSETALPHA 120 120 0 0 Alpha blind offset arcsec TEL TARG OFFSETDELTA 120 120 30 0 Delta blind offset arcsec TEL ROT OFFANGLE 360 360 0 0 Position angle on the sky TEL TARG ADDVELALPHA 15 15 0 0 Differential tracking in RA TEL TARG ADDVELDELTA 15 15 0 0 Differential tracking in DEC TEL AG GUIDESTAR NONE SETUP CATALOGUE Telescope guide star selection FILE CATA LOGUE TEL GS1 ALPHA 0 0 RA of telescope guide star TEL GS1 DELTA 0 0 DEC of telescope guide star TEL SKY OFFALPHA 120 120 0 0 Alpha offset to sky TEL SKY OFFDELTA 120 120 30 0 Delta offset to sky INS MIRR1 NAME isf Ref SkySpider Position INS OPTI1 NAME isf NODEFAULT SPAXEL size arcsec INS SETUP NAME isf NODEFAULT Instrument setup name Hidden parameters SEQ PRESET TF T Preset flag SEQ PUPILTRK TF F Pupil tracking DPR CATG ACQUISITION ACQUISITION Data product category DPR TECH IFU IFU Data product technique DPR TYPE OBJECT OBJECT Data product type Fla
53. ary system is now aligned along the x axis of the FOV and the finest spatial sampling is now along the line joining the two stars RA DEC Equinox and Position angle on the sky define the respective celestial target coordinates and the instrument orientation The target coordinates equinox epoch and the proper motions are entered under the Target section in the OB Under the Obs Description section of the OB the user can enter the parameters which sets up the instrument The position angle on the sky defines the angle between the positive y axis of the SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 60 instrument FOV and the North direction on sky measured Eastwards It is given in the standard astronomical convention N 0 NE 45 E 90 in degrees Note that for PA 0 North up East left the image slices are oriented East West i e you will coarsely sample the field in the North South direction 250 100 or 25 mas per spaxel and obtain a finer sampling of the field in East West direction 125 50 or 12 5 mas per spaxel The relation between PA instrument orientation and spatial sampling are illustrated in Fig 24 Differential tracking is only available for the telescope There is no differential tracking between the natural guide star and the target Accordingly the adaptive optics loop can be only closed on the moving target and not on background stars The value is to be given in units of arcseconds s For s
54. by hot stars Solar analogs for the purpose of removing telluric features are stars with spectral type GOV to G4V These standards have many absorption lines in the IR particularly in the J band The features can be removed by dividing by the solar spectrum that has been degraded to the resolution of the observations In addition to hot stars and solar analogs IR astronomers have used other stellar types as telluric standards For example F dwarfs are commonly used We would like users to think carefully about which star is best for their program Although the observatory will automatically observe a telluric standard for service programs we cannot guarantee that we will make the best choice as this depends on the science users wish to do If you think that a specific spectral type suits your program better than others we recommend that you submit calibration OBs The observatory selects telluric standards from four catalogs the IRIS Photometric Standards the MSSSO photometric standards a composite list of bright spectroscopic standards and the SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 38 Hipparcos Catalog The majority of the standards come from the Hipparcos Catalog Although the Hipparcos Catalog is an excellent source of telluric standards for ISAAC most of the stars in the catalog do not have IR magnitudes which means that IR magnitudes have to be inferred from the spectral type Such an extrapolation lead
55. cally requested this mode in the Phase 1 proposal and after approval given by the OPC 1 4 Glossary Active optics This is the active control of the primary and secondary mirrors of the telescope It is performed using a telescope guide star Adaptive optics This is the correction of wavefront errors induced by atmospheric turbulence The wavefront is measured from a guide star either NGS or LGS see below and the corrections are sent to the deformable mirror within the instrument Although the instrument can run in closed loop without the active optics system controlling the primary and secondary mirrors one gets better adaptive optics performance if the active optics system of the telescope is running Laser Guide Star LGS The artificial star created by the sodium laser at an altitude of 90 km Natural Guide Star NGS The astronomical object used to close the AO loop It is usually a star but it can also be an extended object as long as it provides sufficient contrast at visible wavelengths and fits within the wavefront sensor field of view 2 5 arcsec Pupil tracking Instead of Field Tracking where the sky orientation is kept fixed during an expo sure in Pupil Tracking mode the pupil of the telescope hence the diffraction spikes is fixed with respect to the detector while the sky rotates Tip Tilt Star TTS The star used in LGS mode to sense and correct tip tilt aberrations SINFONI User Manual Version 93 2 VL
56. case the conditions are poor 5 5 Target Acquisition Due to the small FOV of SINFONI and the faintness of many science targets the acquisition is normally done by blind offset from a reference star e g the NGS or Tip Tilt star Therefore unless the target is visible in a short lt 1 minute exposure in the final FOV its centering is crucially determined by the quality of the NGS TTS coordinates In particular currently it is not possible to enter the proper motion of the NGS TTS into the acquisition template hence the user must enter the proper motion corrected coordinates for the NGS TTS or else an imprecise blind offset to the target will be made Note also that very blue stars may be problematic There is no imaging capability in the visible While the AO correction is done in the visible while the science observations and alignments are done in the infrared using the reconstructed image on the RTD it is possible that even when an AO star is bright enough to close the AO loop it may be too faint in the IR for the acquisition and alignment Therefore when choosing the NGS TTS one should make sure that it is sufficiently bright in the observed IR band i e S N gt 3 for DIT 60s The acquisition sequence for observation with AO NGS is the following e Preset the telescope to the target coordinates Set the instrument to the 250 mas scale 8 x8 FOV e Offset the telescope to the NGS guide star e Center the NGS guide star on
57. corresponding to the exposure time of the object Dark frames are used to correct for the instrument bias especially if no off or sky frames are available They are also needed if the OH emission lines are used to track the instrumental flexure In addition dark frames are used to generate bad pixel maps Flat Fields Produced by SINFONI ifs cal LampFlats Flat fields are used to correct for pixel to pixel sensitivity variations A flat field should be generated for each spectral band and pre optics There are several possible types of flat fields Standard flat fields with constant intensities are used to generate master flat fields and static bad pixel maps Linearity flat fields with increasing SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 29 intensity are used to determine the detector s linearity and generate a bad pixel map for highly non linear pixels Flats with an ad hoc DPR keyword FLAT_TECH are also taken together with fiber frames as part of the north south test to compute the detector s distortion Fiber Frames Produced by SINFONI_ifs_tec_NorthSouth Several frames obtained by placing a fiber at different positions Used to determine the detector s geometric distortions and the slitlet distances for each spectral band Arc Lamp Frames Produced by SINFONI ifs cal Arcs Arc lamp frames for wavelength calibration neon argon in K band xenon argon in H xenon in H K and argon in J or alternatively sky frames
58. d interaction matrix of SINFONI e the error budget associated to the instrument mainly optical aberrations of SPIFFI e the resulting Strehl ratios were compared with data taken with SINFONI The predicted Strehl performance in K band on axis is shown in Fig 17 for 4 seeing cases 0 6 to 1 2 at 500nm For other wavelength bands and in cases where the AO guide star is different to the target an approximate correction factor for the anisoplanetism can be found in table 1 The main uncertainty in the conversion between optical seeing and IR Strehl ratios is the undefined coherence time of the atmosphere According to Fig 17 the Strehl ratio at a seeing of 0 8 may vary between 0 2 and 0 4 for a 14th magnitude AO guide star Please note that the exposure time calculator ETC http www eso org observing etc should be used in all cases to estimate the feasibility of your science observations based on the latest performance measurements seeing coherence times long K band Strehl ratio 9 10 11 12 13 14 15 16 17 18 AO guide star R magnitude Figure 17 NGS performance for a wide range of optical seeing values 0 6 to 1 2 and long medium and short coherence times SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 47 Table 1 NGS AO performance Correction factors for anisoplanetism as function of the distance between target and AO guide star together with the corrections of the Strehl ratios for the respective
59. d offset from the AO star A common problem is that the user forgets to take proper motions into account resulting in the target falling of the FOV in cases where the target is too faint to be visible during the acquistion The target proper motions can be entered in the Target section of the OB and this will be considered automatically However since the AO guide or tip tilt star proper motions cannot be entered into the acquisition template the current coordinates corrected for proper motion must be entered The exception is when the AO star is the same as the target in this case the coordinates and the proper motions will be taken from the Target section 12 1 4 SINFONIL ifs acq NGS Within the interactive natural guide star acquisition sequence the 1st step is to center the NGS in the field of view of the 250mas spaxel scale 8 arcseconds field of view In the 2nd step it closes the AO loop and centers the NGS again In the 3rd step it changes the instrument setup to the user selected SPAXEL size and repeats the interactive centering A final 4th step of interactive centering of the scientific target is the final step Some steps can be skipped if the target itself is used as natural guide star or if the 250mas scale was selected for the scientific observations For any NGS fainter than 11 magnitudes it is mandatory that the telescope guide star coordinates SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 are given by th
60. distance arcsec Figure 18 LGS Strehl performance SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 49 9 The integral field spectrograph SPIFFI The integral field spectrometer SPIFFI provides simultaneous spectroscopy of 32x64 spatial pixels with a spectral resolving power of approximately 3000 Three angular resolution scales are available When used with the adaptive optics the angular resolution at a wavelength of 2 2 um is 56 mas milli arcseconds at a scale of 12 5x25 mas spaxel To make optimal use of the spatial elements in seeing limited observations and at partial correction of the atmospheric turbulence with faint reference stars SPIFFI provides image scales of 100 mas pixel and 250 mas pixel Each of the atmospheric transmission bands J 1 1 1 4 um H 1 45 1 85 um and K 1 95 2 45 jum are covered with single exposures In addition the combined H and K bands 1 45 2 45 jum can be observed at a resolution of 1500 With the help of additional mirrors in a system called the sky spider the observer can simultaneously observe the night sky emission from a blank field up to 58 arcseconds off axis This mode is not offered A detailed description of the instrument design can be found in Eisenhauer et al 2003 and Bonnet et al 2004 and references given therein All components are cooled in a bath cryostat to the temperature of liquid nitrogen The liquid nitrogen reservoir sits below the instrument plate 9 1 Pr
61. ducing the lunar illumination FLI constraint to approximately 0 7 and increasing the distance to the Moon to approximately 50 degrees is generally adequate Even here it is important not to over specify the constraints as this reduces the chances of the Observing Block to be executed successfully 1The aperture diameter of the wave front sensor is typically 3 times the measured value of the seeing SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 24 5 4 Weather constraints There is generally no restriction for the transparency except that LGS is only allowed in clear or photometric conditions and at airmass lt 1 5 Adaptive Optics with NGS works in thin clear or photometric conditions however it can be a frustrating experience in thick conditions as AO loop may open many times In thick conditions special care is also needed since any change in flux on the AO MACAO system due to varying sky transparency especially going from thick to clear may cause an automatic shutdown of the MACAOs to prevent an overflux event Apart from the seeing an important factor is the coherence time of the atmosphere The AO system will struggle to correct fast enough if the coherence time is short lt 2 5 ms this is true for both NGS or LGS For service mode observations the instrument operator will decide on whether the conditions are suitable for AO For visitor mode observations you are encouraged to prepare backup OBs with noAO in
62. e RE e 50 Ob Spectrometer Camera ioo sei neamo n wo ho SG 4464 4 46 e 51 A 51 9 7 Detector characteristics uuu duo 9x Aa A 52 10 Software Overview 53 III Reference Material 55 11 The SINFONI science calibration plan 55 11 1 The science calibrations in a nutshell ls 55 12 SINFONI template reference 56 12 1 Acquisition Templates 2 2 2 58 12 11 SPOOL eeh NGS ax chee wa Baw RR RE RORECX TERR RRR AD 60 121 2 SINPON ie acd NGS ne ea eee RE RE REOR Ee 62 12 1 3 LGS acquisition template lt zio be ee bas 63 12 1 4 SINEONI Saeg ROAD esa E a ee 64 12 1 5 RRM acquisition templates 2 5 4 545408 RR RR RR 65 12 2 Science Templates suu x eS AA eke ae SRS OEE A 65 122 1 SINFONI ifs obs FixedSkyOffset 20 uu oom oe oy ox adius 66 12 2 2 SINFONI ifs obs GenericOffset 22s 67 122 3 SINFONI ifs obs AutoJitter 2 44 24 4544 6 be beet ra ee 69 12 2 4 SINFONLifs_obs_AutoJitterSpider 2 2 oll ss 70 12 3 Nighttime Calibration Templates 0 e 71 12 31 SINFOBNLIS cal 5StandardStaf unos o om aeko komm a a 71 1232 SINPORNEIS el PSF oe oea pes eea E da eS 72 123 2 SINFONIIS ea NGS uuu ded ko m de ERE EH EE RAR 72 12 3 4 SINFONLifs_cal_GenericOffset e 73 SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 ix 123 5 SINFONI ifs cal ArcsAtt S sou od Ro 9o ERE RE EE R 74 12 3 0 SIMFONLIIS cal LampFiste ME uu og des xw RR X vp 74 12 4 Daytime Calibration Templates 0050222
63. e axis of the instrument Hence it is not possible to observe companions of very bright stars by placing the primary off the field of view and expect the field to rotate around it Small offsets from the centre of the FOV is possible but the primary s position will drift with time due to the field rotation which must be corrected for during data reduction e Note there is a difference between the way pupil tracking is implemented in NACO and SINFONI For NACO the instrument is automatically rotated in an orientation such that the telescope M2 spiders i e diffraction spikes are always aligned to the x and y axes of the detector For SINFONI the rotator of the instrument simply stops after presetting to a user specified PA on sky so the telescope spiders can be fixed at any orientation It gives more flexibility for the user to choose where best to place the secondary but at the expense of more work in preparation e The combination of small FOV and the large pixels spaxels also means that you will need a fairly large field rotation gt 30 degrees to avoid self subtraction Note also because the spaxels of SINFONI are rectangular twice as tall as wide one gets more sampling if the secondary is placed near 12 or 6 o clock on the FOV Keeping the secondary moving mainly along an image slice i e moving mainly horizontally on the FOV also minimise the effects of image distortion and reconstruction e Another major restriction compared wit
64. e optics Below the sky spider a doublet lens unit collimates the light onto a cold stop for the suppression of the thermal background The stop has a diameter of 6 mm and is equipped with a central obscuration with the equivalent size of the telescope secondary mirror Just in front of the cold stop is the motorized filter wheel housing the four band pass filters which are required to suppress the unwanted diffraction orders of the gratings After the cold stop the motorized optics wheel provides the interchangeable lens systems for the three different image scales and a pupil imaging lens for alignment purposes Each objective consists of two or three lenses All moving functions are driven by five phase stepper motors which have been modified for use at cryogenic temperatures 9 2 Image slicer The focus of the pre optics is located at the small slicer This part of the image slicer consists of a stack of 32 plane mirrors which slices the image into slitlets and separates the light from each slitlet in different directions A second set of 32 mirrors the big slicer collects the light and forms the pseudo slit Figure 20 shows the image slicer To avoid differential thermal contraction the unit is completely made from a zero expansion glass All parts approximately 70 in number are optically contacted No glue is used in the assembly A detailed description of the design and the manufacturing technique can be found in Tecza et al 2003 SP
65. e users Telescope Guide Star Selection that inaccuracies 1 in the telescope and or AO guide star coordinates cause the target to fall off the small field of view of SINFONI For brighter targets we expect to detect a few speckles SETUPFILE The reason for this is within the field of view to allow an interactive centering in open loop SINFONIL ifs acq NGS Interactive Natural Guide Star Acquisition Parameters to be specified Parameter Range Default P2PP Label TEL TARG ALPHA NODEFAULT RA TEL TARG DELTA NODEFAULT DEC TEL TARG EQUINOX 2000 Equinox DET DIT isf NODEFAULT Integration time DIT DET NDIT isf NODEFAULT Number of Integrations NDIT SEQ NGS DIT isf NODEFAULT NGS integration time DIT SEQ NGS NDIT isf 1 NGS number of Integrations NDIT SEQ NGS ISTARGET TF NODEFAULT Target AO Guide Star SEQ NGS ALPHA NODEFAULT RA of AO Guide Star SEQ NGS DELTA NODEFAULT DEC of AO Guide Star SEQ NGS MAG 2 25 12 R mag of AO Guide Star SEQ NGS COLOR 1 5 NODEFAULT NGS B R color SEQ NGS FWHM 0 10 0 0 FWHM of AO Guide Star arcsec SEQ PUPILTRK TF F Enable this for pupil tracking TEL ROT OFFANGLE 235 235 0 0 Position angle on the sky TEL TARG ADDVELALPHA 15 15 0 0 Differential tracking in RA TEL TARG ADDVELDELTA 15 15 0 0 Differential tracking in DEC TEL AG GUIDESTAR NONE SETUP CATALOGUE Telescope guide star selection FILE CATA LOGUE TEL GS1 ALPHA 0 0 RA of telescope guide star TEL GS1 DELTA 0
66. ec SEQ NGS SNR 0 0 10000 0 1000 0 Minimum S N for AO guide star SEQ NGS USELASTSKY TF T Use for WFS the last measured sky value SEQ PRESET TF T Preset flag DPR CATG ACQUISITION ACQUISITION Data product category DPR TECH IFU IFU Data product technique DPR TYPE OBJECT OBJECT Data product type NGS parameters same as interactive acquisition The parameters for the AO guide star are a logical flag Science Target AO Guide Star and the coordinates of the AO guide star in RA and DEC with the same Equinox as that specified in the Target section of the OB Furthermore the approximate size of the AO guide star 0 for point sources only specify the size if you expect it to contribute significantly with respect to the seeing and the approximate magnitude and color of the AO guide star have to be selected These parameters are required to properly set up the AO system with respect to aperture size of the WFS and differential atmospheric refraction between the visual light WFS and the IR spectrograph As noted in 12 1 it is important to consider the proper motion of the NGS especially for faint targets since the NGS is also used for blind offset to the target therefore the entered coordinates must be corrected for proper motion for the expected date of observation there is currently no easy way to enter the proper motions of the NGS into the acquisition template 12 1 3 LGS acquisition template For the general user the LGS te
67. ens the incoming WF and the WFS measures the residual WF error SINFONI as well as CRIRES and the VLTI MACAO systems is using a Curvature WFS The curvature sensor is designed to measure the WF curvature as opposed to the WF slope This is SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 34 Observed object Plane wavefront _ Atmospheric turbulence Corrugated wavefront y Uncorrected image Deformable mirror Tip tilt mirror e N Gs Real Time 2 X Computer 2 Wavefront em SURE Y KI AO corrected mage Corrected wavefront al Camera high resolution image Figure 8 Principle of Adaptive Optics Note that in practice and contrary to this schematic design SINFONI has no dedicated Tip Tilt mirror but performs low and high order corrections with a single deformable mirror mounted on a tip tilt stage achieved by comparing the plane irradiance distributions of two planes placed behind and before the focal plane In practice a variable curvature mirror membrane is placed in the telescope focus By vibrating inside and outside focus blurred pupil images can be imaged on a detector array in SINFONI s case a lenslet array feeding avalanche photo diodes APDs The modulation frequency of the membrane corresponds to the temporal sampling frequency of the WFS The difference between the inside and outside pupil image measures the local WE curvature The performance of an A
68. ervice mode observations an ephemerides file needs to be provided Please consult the P2PP manual concerning the format and submission procedure Telescope guide stars are either selected from the CATALOG s available at the telescope or selected by the users if the option SETUPFILE was selected Telescope offset RA DEC to sky These keywords define the position where the sky field is to be observed if set to values 0 The sky exposure is taken before starting the interactive target identification If the value is set to 0 the step is skipped and the overhead time is shortened It may not be the best choice to skip the sky for faint targets of J H K H K gt gt 15 Important note on coordinates The coordinates of the telescope guide star the target and the natural guide star or the tip tilt star of the AO system should be measured with an accuracy of a small fraction of the SINFONI field of view Good proper motion measurements are essential especially for the smallest FOV 0 8x0 8 arcsec As during the acquisition process one centers the natural guide star or tip tilt star to the centre of the FOV before offsetting to the target field using the offsets calculated from the coordinates it is therefore important to consider the proper motion of the target as well as that of the alignment star While bright targets can be repositioned on the FOV as the last step of the acquisition faint targets will have to rely on the blin
69. es concerning information on the AO guide star e t requires the absolute coordinates of the AO guide star i e corrected for proper motion Unless you tick the box Target AO Guide Star in which case it will use the target and use the proper motion information of the target e t also asks for the B R color of the AO guide star This is used to compute the guiding wavelength for the field selector holding the AO guide star Which in turn is used to correct for atmospheric refraction effects e t requires the FWHM measured in R band images or at similar wavelength of the AO Guide star in order to optimize a diaphragm in the AO system This diaphragm is set as a function of the seeing such as to optimize the amount of light received from the object with respect to the amount of background light from the sky If your object is a point source leave this to be O only the seeing will be taken into account Only if your AO guide star is significantly extended with respect to the seeing i e comparable to the seeing value this optimization parameter will have a noticeable effect e For LGS Seeing Enhancer mode even though a Tip Tilt Star is not required for the AO due to a current bug its RA and DEC should not be left to the default values of 000000 0 000000 0 or a software error will occur during execution Until the bug is fixed please set them to the RA and DEC of the target Science The science templates are standard if
70. fed by a curvature sensing adaptive optics module The spectrograph operates with 4 gratings J H K H K providing a spectral resolution around 2000 3000 4000 in J H K respectively and 1500 in H K each wavelength band fitting fully on the 2048 pixels of the Hawaii 2RG 2kx2k detector in the dispersion direction The SINFONI field of view on the sky is sliced into 32 slitlets Pre optics allow to chose the angular size of the slices on the sky The choices are 250 mas 100 mas and 25 mas leading to field of views on the sky of 8 x8 3 x3 and 0 8 x0 8 respectively Each one of the 32 slitlets is imaged onto 64 pixels of the detector Thus one obtains 32 x 64 2048 spectra of the imaged region of the sky Typical limiting magnitudes S N 10 in 1h on source are around 17 18 mag in J H K SINFONI can be used without adaptive optics guide star in which case the AO module just acts as relay optics and the spatial resolution is dictated by the natural seeing In that case the recommended slice width is 250 mas for a 8 x8 field of view The full power of the instrument is of course achieved when an adaptive optics guide star is available For best correction the star should be brighter than R 11 mag However the AO can work and will provide a moderate image quality improvement with stars as faint as R 17 mag in the best conditions Ideally the AO guide star should be as close as possible to the scientific target if
71. field of view The latter is done by an interactive target identification loop on the reconstructed images Furthermore the acquisition sequence will start the adaptive optics in closed loop mode NGS templates or flatten the deformable mirror which is required to achieve excellent image quality in open loop mode noAO template The deformable mirror is flattened with the light from the calibration fiber Unlike for other instrument there are no data stored and archived on the disk during the target acquisition sequence The detector is continuously read to save the data acquisition overheads Optionally a sky subtraction frame can be stored not being saved to disk in an offset field for faint targets The open loop noAO acquisition template also offers the option to execute a blind end offset from a reference star to the science target Here we describe the template keywords common to all target acquisition templates whereas the more specific keyword parameters are describe later together with the respective template where they are used SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 59 DIT and NDIT are the user defined Detector Integration Time and the number of DITs to be integrated before writing the data to the disk The science templates which involve nodding to sky allow different values of NDIT for target and sky respectively NDIT OBJECT and NDIT SKY SPAXEL size and Instrument setup name define the SINFONI inst
72. following must be consid ered e Pupil tracking will work with NGS mode only It can work with all filters and grating combi nations However at time of writing December 2013 we have only tested the 25 mas scale 0 8 x0 8 FOV The 100 mas 3 2 x3 2 and 250 mas 8 x8 scales remain untested but with these 2 scales the PSF will be under sampled Therefore for most situations the 250mas scale is not suitable for S ADI The 100 mas scale may be usable but one could consider making sub pixel offsets between exposures to have some sampling of the PSF or perhaps it is unnecessary SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 12 5 sigma contrast curve on Cube1 no secondary injected 5 sigma contrast A 0 007F S ids HIP69845 S FITTTTTTTTTTTTTTTTT TTTTTTTTTTTTTTTTTTITTTTTTTTTTTTTTTTTTTITTTTTTTTT Artefact due to SINFONI partial field overlap after PSF centering and rotation 0 003 0 002 0 001 Figure 5 5 o contrast curve based on sub cube 1 with no secondary injected e The 25 mass scale has the disadvantage that due to the small FOV 0 8 x0 8 with the star is put at the centre of the FOV then one can only find companions about lt 0 3 from the primary e Pupil tracking only works with the primary star on axis only In particular there is no way to place the primary off the FOV and have the field to rotate around it the field will always rotate around th
73. g PSF_ Other generic naming conventions common to all ESO instruments in service mode are PRE pre imaging ToO target of oportunity MOV moving target CAL calibration star for RV flux e The magnitude of the brightest object in all fields including standard stars should be ex plicitly given in the README file or otherwise indicated on the Finding Charts e For OBs which require the observations to be centred around meridian transit e g Pupil Tracking the OB name should have the suffix MERIDIAN appended SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 23 5 Observing with SINFONI at the VLT 5 1 Overview As with all other ESO instruments users prepare their observations with the p2pp software Acqui sitions observations and calibrations are coded via templates Sec 12 and two or more templates make up an Observing Block OB OBs contain all the information necessary for the execution of an observing sequence At the telescope OBs are executed by the instrument operator SINFONI and the telescope are setup according to the contents of the OB The SINFONI Real Time Display is used to view the raw frame as well as the reconstructed images During acquisition sequences it is mostly used in reconstructed image mode for a proper centering of the targets in the field Daytime calibrations are automatically executed in the morning following the observations 5 2 Visitor Mode Operations Informa
74. get properly flagged calibration data frames in the archive Please find the explanation of the parameters within the description of the GenericOffset template SINFONI_ifs_cal_PSF PSF calibration star observation Parameters to be specified Parameter Range Default P2PP Label DET DIT 0 3600 NODEFAULT Integration time DIT DET NDIT LIST isf NODEFAULT List of number of integrations NDIT SEQ NOFF 1 100 NODEFAULT Number of offset position SEQ OBSTYPE LIST Os NODEFAULT List of observation types O or S SEQ OFFSET COORDS SKY DETEC SKY Offset coordinate type selection TOR SEQ OFFSET1 LIST NODEFAULT List of offsets in RA or X SEQ OFFSET2 LIST NODEFAULT List of offsets in DEC or Y SEQ SPECDITH TF F Spectral dithering INS OPTI1 NAME isf NODEFAULT SPAXEL size arcsec INS SETUP NAME isf NODEFAULT Instrument setup name Hidden parameters SEQ RETURN TF T Return to Origin T F DPR CATG CALIB CALIB Data product category DPR TECH IFU NODDING IFU NODDING Data product technique DPR TYPE PSF PSF Data product type CALIBRATOR CALIBRATOR 12 3 3 SINFONI ifs cal NGS The output files of this template are thought to serve as PSF reference data like for the PSF template Here for the NGS template the data is taken in the field of the science observations with the NGS which was selected for the adaptive optics The template will setup the field selector mirror and telescope from the target back to the
75. h NACO is the need to avoid persistence on the detector which means one should keep the maximum count in the spectral continuum below about 6000 8000 AUDs per DIT see 8 2 6 for the actual limits This means that for the 25mas scale and minimum DIT the limits for J H K and H K are 5 0 5 0 4 4 and 6 0 SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 13 450 contrast curves IDPS controst curve examples median SINFONI 5a detection mag 0 2 4 6 8 10 Separation arcsec Figure 6 Expected contrasts from SINFONI blue shaded region compared to example contrast curves from the International Deep Planet Survey Galicher et al 2012 mag respectively note that these are quoted for guidelines only you should use the Exposure Time Calculator to check the actual peak counts e Given the minimum DIT is 0 83 seconds and frames are read out individually i e no cube mode much care must be made in the target selection There is no coronograph on SINFONI and persistence must be avoided since in the worst case it can last for many days ruining the observations of the other observers Ideally one should ask in the README for the observations to be done at the end of the night to minimise the possibility of other people s observations being affected by any persistence effects e To minimise overheads and maximise the S N and to avoid smearing out too much the signal for a fast rotator one would usually limi
76. he initial sky position and therefore identical to those of the target jitter box There is an option to change the Number of exposures per offset position such that the template takes NEXPO number of jittered exposures before nodding between the object and sky position This should be rarely needed for the long exposure times of the SINFONI IFS mode observations For a given number of AB cycles the exposure time would be DIT NEXPO NDIT for the object NDIT for the sky Number of AB or BA cycles The number of archived exposures will be 2 Number of AB or BA cycles One half of these files are taken on the object These numbers are to be multiplied by the Number of exposures per offset position if set to a value different from 1 Twice the number of frames are taken if the spectral dither option is selected SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 67 SINFONI_ifs_obs_FixedSkyOffset IFS with jitter and nodding Parameters to be specified Parameter Range Default P2PP Label DET DIT 0 3600 NODEFAULT Integration time DIT SEQ JITTER WIDTH 0 8 NODEFAULT Jitter box width SEQ NABCYCLES 1 100 NODEFAULT Number of AB or BA cycles SEQ NDIT OBJECT 1 10000 NODEFAULT NDIT for the OBJECT positions SEQ NDIT SKY 1 10000 NODEFAULT NDIT for the SKY positions SEQ NEXPO 1 1000 1 Number of exposures per offset position SEQ SKY OFFSETALPHA 3600 3600 NODEFAULT Alpha offset for Sky
77. he sky RA DEC or the Detector X Y Note also that the offset direction is different between DETECTOR or SKY offset coordinate types DETECTOR offsets defines how the object moves relative to the detector i e the FOV while SKY offsets define the offsets in RA and DEC applied to the telescope For example a detector offset of 1 1 moves the object 1 in X and 1 in Y with respect to the FOV For PA 0 a 1 1 sky offset moves the telescope 1 East and 1 North i e with respect to the FOV the object will move 1 in X but 1 in Y For more information please see an example in 12 2 2 and Fig 26 Note that the templates use cumulative offsets That is your position at a given time is derived from the sum of all offsets specified so far in the template For example the series of offsets 0 10 0 10 brings you back to the original position in the last exposure If the target is centred on the FOV this example series could correspond to an exposure on target followed by two sky exposures 10 away and then returning to the target in the fourth exposure SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 27 5 9 Instrument and telescope overheads The telescope and instrument overheads are summarized below Hardware Item Action Time minutes Paranal telescopes Preset 6 Paranal telescopes Offset 0 25 SINFONI Acquisition no AO 3 SINFONI Acquisition AO NGS 2 A DIT NDIT SINFONI Acq
78. he spectrum of the telluric standard should be known so that features belonging to it can be removed However this is not normally the case so one has to use standards in which the spectrum is approximately known In general we use either hot stars or solar analogs as telluric standards and generally these stars are selected from the Hipparcos Catalog The spectra of hot stars those hotter than B4 are relatively featureless and are well fit by blackbody curves So by knowing the spectral type of the star one uses a blackbody curve with the appropriate temperature to fit the continuum of the standard The spectra of stars that are cooler than AO start to have many more features and cannot be fit with a blackbody curve for wavelengths below 1 6 microns Unfortunately hot stars do contain some features usually lines of hydrogen and helium that can be difficult to remove If the region around the hydrogen and helium lines are of interest then one can also observe a late type star which should have weak hydrogen and helium lines This star is then used to correct for the helium and hydrogen absorption in the spectrum of the hot star Some hot stars also have emission lines or are in dusty regions These stars should be avoided The V I colour of the star can be used as an indicator of dust For stars hotter than AO it should be negative And lastly hot stars tend to lie near the galactic plane so there may be situations where there are no near
79. http www eso org sci facilities paranal sciops Paranal Science Operations Nevertheless we list here a few points that might be useful when thinking about the upcoming preparations of your Phase 2 material The good news is that unlike several other instrument on the VLT preparing observations for SINFONI does not require any extra preparation software beyond the standard Phase 2 tools 4 1 Do you have all information in hand A few considerations before starting the observation preparation phase e The exact coordinates of your targets SINFONI has a very small field of view and it is very easy to miss the target e Good coordinates for the NGS TTS guide stars and noAO reference stars especially their proper motions This is especially important for faint targets which are not expected to be visible during the acquisition Since the instrument does a blind offset from the NGS TTS noAO reference star any error and proper motions in its coordinates will directly translate to the target field A common user mistake is to forget to take into account the proper motions in the OBs Note that for cases where the target is not the same as the AO guide star since the proper motions of the guide star cannot be entered into the NGS or LGS acquisition templates you must calculate and enter the real RA and DEC at the time of the observations For cases where the target coordinates are taken from the Target field of the OB e g Target AO star
80. ides the following functions e The Y stage selects the mode of operation Normal nothing in the optical path Flat fielding flat folding mirror in the optical path Point source calibration mode fiber inserted in the path e The X and Z table together with the Y table allow a fine positioning of the point source in the field and along the focus axis The fiber can be freely positioned in a cube with 25mm edge size around the Cassegrain focal plane The Calibration unit consists in an integrating sphere with a 50mm diameter output port providing a flat field to SPIFFI In normal operations a shutter closes the sphere The integrating sphere provides also two fiber ports One fiber will be guided from the sphere to the Linear Unit Focal Plane the other to the LGS trombone for WFS calibration The light sources are 4 PenRay lamps Xenon Argon Neon Krypton and a halogen lamp with regulated output power The light sources are mounted in a lamp house To avoid problems with the excess heat of the lamps the lamp housing is mounted to the AO Housing The light is guided to the integrating sphere by a gold coated tube 50mm diameter SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 46 8 2 AO module System Performances 8 2 1 NGS performances The Strehl performance achieved in NGS mode has been evaluated for on axis observations by combining e simulated atmospheric turbulance model together with the measure
81. ield of view top is sliced into small slices which are recombined into a pseudo longslit before being dispersed The dispersed planes can be recombined to form an image or used to extract a spectrum at any position within the field of view Note that for SINFONI slice number 1 corresponds to the BOTTOM slice in the FOV and the slice number increases upwards i e the opposite to the graph above Also on the detector the wavelength increases downwards not upwards as in the graph above SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 39 The main benefits of using an IFU instrument are gained when observing extended objects There are two typical cases in which IFU observations are much more efficient than those done with a single slit e Observing objects which are on a scale similar to that of the field of view here the benefits are obvious a single SINFONI observation will be equivalent to 32 single slit observations e Smaller objects with an unknown spectral structure this refers to objects which are smaller than the field of view but which contain an unobserved spectral structure e g a velocity gradient With a single slit several observations would have to be made at different angles to ascertain the spectral structure With SINFONI one observation would be all that is needed SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 40 8 The Adaptive Optics Module 8 1 AO Module System Description 8
82. in NGS LGS and for noAO OBs then the proper motions should be entered into the Target section in the OB e f you observe in the NGS mode with a science target different from the AO guide star it is strongly recommended to use coordinates for the AO guide star and science target from the same catalog reference system Further the AO guide star coordinate should be accurate enough such that it is visible during the acquisition performed with the 8 x8 field of view taking into account that the VLT pointing could be off by 1 2 e f you observe in the LGS mode please refer to section 2 2 SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 19 e f you observe a faint target without an AO guide star you have two possibilities 1 to specify the telescope guide star in your acquisition template and provide the target coordinates in the same reference system this will guarantee a pointing to typically 100 200 mas Or 2 to point to a bright nearby star and perform an offset from this star at the end of your acquisition For this latter solution the coordinates of your target and the bright star must be defined accurately and in the same reference system e You should put some careful thinking into the plate scale that you will use Are your ob servations driven by the available field of view Or do you need the highest possible spatial resolution available e You should have decided on the best strategy to obtai
83. ined by the parameter Number of offset positions This number maybe different from the number of elements in the aforementioned lists Lists do not have to have the same length If the number of offset exposures is larger than the length of the list then the list is restarted from the beginning until the correct number of frames have been acquired The total integration time is DIT times the sum of the NDIT taken at the specified Number of offset positions The lists may also be longer than the Number of offset positions but these surplus offsets will be ignored by the system It is good practice to use lists of equal length or lists which contain only one parameter if one of the parameters shall remain unchanged like NDIT Warning Make sure that you do not have offset positions for type O exposures outside of the range of the field selector SINFONT ifs obs GenericOffset Parameters to be specified IFS with user defined offsets Parameter Range Default P2PP Label DET DIT 0 3600 NODEFAULT Integration time DIT DET NDIT LIST isf NODEFAULT List of number of integrations NDIT SEQ NOFF 1 100 NODEFAULT Number of offset position SEQ OBSTYPE LIST OS NODEFAULT List of observation types O or S SEQ OFFSET COORDS SKY DETEC SKY Offset coordinate type selection TOR SEQ OFFSET1 LIST NODEFAULT List of offsets in RA or X SEQ OFFSET2 LIST NODEFAULT List of offsets in DEC or Y SEQ SPECDITH T
84. ing The template is only in one aspect different to the SINFONI ifs obs AutoJitter It allows to select with the parameter SkySpider Position the respective position of the periscopic sky spider mirror in front of the image slicer The template would mark the acquired data with the flag DPR TECH like IFU SPIDER Since the template is identical in all other aspects we refer to the AutoJitter template for a description of the parameters SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 71 SINFONI_ifs_obs_AutoJitterSpider IFS with jitter and sky spider Parameters to be specified Parameter Range Default P2PP Label DET DIT 0 3600 NODEFAULT Integration time DIT DET NDIT isf NODEFAULT umber of Integrations NDIT SEQ JITTER WIDTH 0 8 NODEFAULT Jitter box width SEQ NEXPO 1 1000 1 Number of exposures per offset position SEQ SPECDITH TF F Spectral dithering INS MIRR1 NAME isf Ref SkySpider Position INS OPTI1 NAME isf NODEFAULT SPAXEL size arcsec INS SETUP NAME isf NODEFAULT Instrument setup name Hidden parameters SEQ POISSON 1 100 10 SEQ RETURN TF T Return to Origin T F DPR CATG SCIENCE SCIENCE Data product category DPR TECH IFU SPIDER IFU SPIDER Data product technique DPR TYPE OBJECT OBJECT Data product type 12 3 Nighttime Calibration Templates There are 5 templates available to calibrate during the night The StandardStar template can be used for any kind of standard star
85. ion defines if the user selected offsets are executed with respect to the detector XY coordinates or the sky RA DEC coordinates The offsets are defined as list of parameters List of offsets in RA or X and List of offsets in DEC or Y respectively The offsets are cumulative relative to the previous position If the parameter Offset coordinate type selection SKY then the offsets have to be considered and specified as telescope offsets following the offset conventions and definitions given in section 5 8 If the parameter Offset coordinate type selection DETECTOR the offset sequence as given in List of offsets in RA or X and List of offsets in DEC or Y specifies what the target is doing on the detector For an example please see Fig 26 Additionally the observation type and the number of integrations NDIT can be defined for any of the object or sky positions in the parameters List of observation types O or S and List of number of integrations NDIT respectively In case of type O the archived data files are flagged as SCIENCE and the AO loop is closed for AO observations NGS LGS and SE mode In case of type S the archived files are marked as SKY and the loop is opened to allow offsets beyond the range of the field selector mirror which images the science field to the spectrograph image slicer while the NGS TTS is centered on the WFS The total number of exposures is def
86. ke the DM is mounted to a Tip Tilt Mount TTM designed and built by OBPM which provides 240 arcsec a mechanical stroke i e 3 6 arcsec on the sky with a 100Hz 3dB closed loop bandwidth Fiducidal marks 05x2mm 453 gt 3 fu EN 4 Fiducidal mark 0 5x 2 mm YE E s NE x gt 55 se Figure 13 DM electrode geometry DM TTM assembly 8 1 4 The Wavefront Sensor The following functions are sequentially implemented in the wavefront analyzer e Extraction of the reference star beam Field Selector e Projection of the reference star image on the Membrane Mirror Imaging Lens e Scan of the intra and extra pupil regions by modulation of the Membrane Mirror curvature e Creation of a pupil image centered on the Lenslet Array e Reduction of the flux for bright reference stars to within the linear range of the APDs by means of Neutral Densities NDs wheel e Re imaging of the 60 sub pupils on the 60 fiber cores core diameter 100 jum by the Lenslet Array e Injection of the collected beams in the 60 APDs The scanning lens of the field selector is mounted on an XYZ table the XY axes enable the guiding star to be selected in the 1 x 2 FOV while the Z stage compensates for the VLT field curvature The position of the Field Selector defines the reference for the pointing Since SINFONI is mounted at the
87. linerarity bad pixel map Distortion data gt 70 monthly series of images of the calibration fiber while moved in y direction over the image slicer not within the SINFONI calibration plan by user request only PSF standard n on request to determine instrumental AO PSF Flux standard n on request to determine overall system transmission telluric standards of known magnitudes may be used n number determined by user SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 56 12 SINFONI template reference All scientific and calibration observations with ESO instruments are prepared as observing blocks OBs with the phase 2 proposal preparation tool P2PP The scheduling of these OBs is then done on the site with the broker of observing block BOB and p2pp in visitor mode and with bob and the observation tool OT during service mode observation runs Observing blocks consist of the target information a small number of user selected templates the constraints sets and the scheduling informations The observing templates which are described below are lists of keywords parameters of the respective templates to define the configuration and setup to be used for the respective observations Parameters can be either selectable by users or they are hidden to the user to compact and to simplify the appearance of the parameter lists Hidden parameters cannot be changed by the users but only by the instrument operato
88. lux standards close in airmass and time with respect to the science observations another example of standard stars are velocity standards Please find the explanation of the parameters within the description of the GenericOffset template SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 SINFONI_ifs_cal_StandardStar Standard star calibration observation Parameters to be specified Parameter Range Default P2PP Label DET DIT 0 3600 NODEFAULT Integration time DIT DET NDIT LIST isf NODEFAULT List of number of integrations NDIT SEQ NOFF 1 100 NODEFAULT Number of offset position SEQ OBSTYPE LIST OS NODEFAULT List of observation types O or S SEQ OFFSET COORDS SKY DETEC SKY Offset coordinate type selection TOR SEQ OFFSET1 LIST NODEFAULT List of offsets in RA or X SEQ OFFSET2 LIST NODEFAULT List of offsets in DEC or Y SEQ SPECDITH TF F Spectral dithering INS OPTI1 NAME isf NODEFAULT SPAXEL size arcsec INS SETUP NAME isf NODEFAULT Instrument setup name Hidden parameters SEQ RETURN TF T Return to Origin T F DPR CATG CALIB CALIB Data product category DPR TECH IFU NODDING IFU NODDING Data product technique DPR TYPE STD STD Data product type 72 12 3 2 SINFONI_ifs_cal_PSF This template may be used by observers who require special PSF standards Since the template is identical with the GenericOffset template we will keep the description as short as it can be It is offered to
89. ly monitors this ftp directory When it detects a file it checks if the filename corresponds to an approved activation code If this is the case and if the required instrument is currently used at the telescope the on going observations are ended and a new BOB starts an OB with the same name as the ftp file The telescope automatically presets to the coordinates specified in the ftp file and the requested observations are performed straight away Pls of approved SINFONI ToO programs requesting this mode need to prepare their OBs in the usual way However these RRM programs use specific acquisition templates described in the template section of this manual 12 Although commissioning activities occurred until 2008 the Laser Guide Star LGS facility has been offered to SINFONI users as early as P79 mostly in service mode This mode provides significant improvement for programs which were limited to the no AO mode due to the lack of an adequate natural guide star for the AO system Please note nevertheless that LGS observations can only be done under clear sky conditions and still require the use of a Tip Tilt Star TTS to reach optimal correction Moreover the airmass must be less than 1 5 At the time being Strehl improvement up to 20 have been measured under the best seeing conditions TTS with R lt 17 have been successfully used with separations from the science target as large as 1 arcmin LGS can only be used for programs having specifi
90. magnitudes in J H and K and 6th magnitude in H K In closed loop NGS observations neither the target nor the natural guide star must be brighter than these magnitudes unless the fast acquisition template is used in which case the limits are brighter by 1 and 2 magnitudes for the 0 1 pix and 0 025 pix scales respectively These limits are set to avoid saturation during the acquisition which is by default taken with the widest 8 x8 scale In visitor mode the acquisition on the widest scale may be avoided with the template SINFONI_ifs_acq_NGS This will however require excellent co ordinates and additional precaution at the end of the observation when presetting to the next target Note The detector can show a strong persistence effect even after being illuminated below the saturation level typically 10000ADUs To exclude any risk of artefacts produced by wavelength dependent detector persistence DITs must be selected such that fluxes are at most 8000 ADUS DIT pixel for K 7000 ADUs DIT pixel for H and H K and 6000 ADUs DIT pixel for J throughout the spectral range covered Please note that if illumination was close or beyond saturation the time scale to recover from the persistence is longer than an observing night in fact as shown in Fig 2 after such a worst case saturation event persistence artefacts can last up to several days and severely affect subsequent observations both science and calibrations 2 7 Total instrument
91. mended DITs and NDITS Object Sky pattern For long exposures on faint targets in which no saturation risk is given we recommend to work with NDIT 1 and a DIT depending on the frequency with which the sky should be obtained For exposure times longer than 150s it is mandatory in service mode to select the DIT from the recommended values of 150 s 300 s 600 s or 900 s For short exposures we recommend DIT values of 0 83s 1s 2s 5s 10s 15s 20s 30s 60s or 1005s to reduce the calibration load and to share the calibration data with other projects The standard templates support an ABBA pattern that is Object and Sky frames are alternated with 50 of the total time spent on the object Observation sequences with Object Sky patterns in which less time would be spent on the sky is commonly used when bright objects are observed For a source fairly isolated and significantly smaller than the used SINFONI field of view e g a source significantly smaller than 8 x 8 there exists the possibility to obtain the sky background measurements within the field of view by applying offsets to place the target successively into the four quadrants of the detector while simultaneously monitoring the sky background in the other three in the ideal case entirely empty quadrants 2 9 Pupil Tracking Mode From P93 onwards a mode Pupil Traking will be offered allowing the S ADI Spectrocopic ADI technique to obtain spectra images of faint com
92. mert SI6L T 1 geet met DER gert PO B o P 3 g g E FP INN 3 5 W A D L DR 0969 T 08691 oer met spon T T p T sgp T 0969 T SEBIT T stert T 09691 T sgp T 3 QM LSI RENO ON REZ veer Seve oer mmer DA AER d veer oer veer SEST mer s 8g SS E r LP LL S S 9 S S S S dn dd DR sten 09691 Se69T T DER T sgp T s 11 TSE 1 TTT TH L veer sera veer SEST mmer RET OSLyT vert Seu T T OFLFT T out T ot T Seu T T mt T ot T gout T SELFI mt T out T gout T S Z S S Ss S Ss Mm Nn O z E T a y B So cu SE E B CH az O e e Lei T Mm Lin z 73 Figure 29 Spectral point spread function in the H band For the three different plate scales for three regions on the detector top to top top to bottom on detector SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 80 4 aerz gerz srs SES LEY ESAS vers seve wers qaer ger 7 d seva T sere T dd d RT PRI as 08773 T 14 T Ld T 1 vom z mars osorz OLOTZ RB S 858 B 5 SES 5385888 HOH E TITTITTTTTTT N
93. mirror f D 1 2 8 design The diameter of the three big lenses is 170 mm All lenses have a multi layer anti reflection coating optimized for the wavelength range from 1 05 2 45 m 9 6 Sky spider The light enters SPIFFI from the top and first passes the sky spider This device contains three motorized pairs of mirrors which reflect the light from an off axis sky field onto the image slicer SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 52 field of view The projected distances of the sky positions from the field centre are 19 38 and 58 arc seconds A forth position may be used for an upgrade with a coronographic mask See Fig 22 for the positions of the sky spider on the SPIFFI field of view This mode is not offered Figure 22 The positions of the sky spider arms on the SPIFFI FOV NB only one arm may be used at a time and its coverage of the field is user selectable 9 7 Detector characteristics The instrument has been upgraded since February 2005 with a science grade Rockwell Hawaii 2RD detector 2kx2k The charactierical parameters are summarized below The detector is permanently read in none destructive mode For integration times of DIT 100s the noise level is down to 7 e at longer DIT the noise is dominated by Poisson noise from the dark current thermal background and remnance effects Parameter Detector Rockwell Hawaii 2RD Operating Temperature 189 degrees Celsius Gain 2 42 0 05 e A
94. mplate is very similar to the NGS template the only difference being that the Tip Tilt Star TTS is replaced by the AO guide star The same warning applies for the accuracy of the TTS coordinates and the need to manually correct for its proper motion For AO correction an R magnitude brighter than 17 mag is required with good corrections obtained if SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 64 R lt 14 mag Select Perform acquisition in seeing enhancer mode for LGS observations without Tip Tllt correction Note that for LGS Seeing Enhancer mode even though a Tip Tilt Star is not required for the AO due to a current bug its RA and DEC should not be left to the default values of 000000 0 000000 0 or a software error will occur during execution Until the bug is fixed please set them to the RA and DEC of the target Pupil tracking is not offered for LGS observations 12 1 4 SINFONI ifs acq noAO The open loop noAO acquisition template will preset the telescope to the target or reference star for blind offset acquisitions setup the instrument to the selected wavelength range and the wide 250mas SPAXEL scale After the deformable mirror is flattened with the calibration fiber the interactive target centering is started First the target is centered on the 250mas scale and then on the user selected SPAXEL scale Optionally a sky frame can be taken in an offset field The template also provides blind offsets c
95. n compensation The WFS corrects the telescope guiding for the atmospheric refraction difference between its optical guiding wavelength and the near infrared central wavelength of the spectrograph set up Once the response curve of the WFS is taken into account the optical guiding wavelength can be derived from the B R color as follows Guiding wavelength nm 590 40 B R The observation software will take care of the guiding wavelength once the color is entered into the observation templates 2 2 Laser Guide Star LGS observations This section provides the necessary information for Phase preparation using LGS Additional in formation may be provided on the SINFONI website http www eso org sci facilities paranal instruments sinfoni to which you are encouraged to check Please note that LGS observations can only be carried out under clear CLR or photometric PHO observing conditions at airmass lt 1 5 Thus objects with declinations south of 70 degrees and north of 20 degrees cannot be observed In normal LGS mode a Tip Tilt Star TTS is required for tip tilt measurements of the wavefront The TTS needs to be located within a strict maximum distance of 1 arcmin from the science target the field accessible to the Strap Field Selector is 1 x2 see previous section for a description of the field selector orientation The TTS should also be brighter than R 17 mag ideally in the range R 12 13 5 mag Note that the cor
96. n recipe si rec psf and standard star frames in si rec stdstar When manually using the pipeline through esorex or gasgano they can be used interchangably Science Frames Produced by SINFONI ifs obs AutoJitter SINFONL ifs obs FixedSkyOffset and SINFONI ifs obs GenericOffset Science object frames Can be used to generate publications 6 1 3 Calibration Products Bad Pixel Maps Bad pixel maps determined with different methods may be combined to produce a more accurate bad pixel map Static bad pixel masks are generated from dark frames or flatfields and they are used to interpolate the bad pixels Dynamic bad pixels or cosmic rays are hopefully rejected by building clean means of several frames if not the reduction is highly affected by them due to error SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 30 propagation during interpolation Quality of the bad pixel map is important to the quality of the end products and especially the wavelength calibration and distortion determination are sensitive to the quality of the bad pixel maps Since bad pixel maps are not expected to vary rapidly maps from the calibration data base has been used with good results Distortion A fits table containing the coefficients for distortion correction Geometric distortion depends on the spectral band used and is corrected for in stacked frames in North South tests wavelength calibrations and science data reduction In principle
97. n sky measurements Note that unlike long slit spectrographs the field of view except maybe the largest one is too small to nod and keep your object in the field of view l e no nod on slit can be done Thus your sky measurements have usually to be obtained from offset fields and the templates allow you several option see Section12 The frequency with which to obtain sky measurements depends on the band more frequent in J and H less frequent in K and on the accuracy with which you want to subtract them variations of the order of minutes are usual thus sky measurements could vary from anything between every 120s to every 600s choose the same DIT and vary the NDIT only if noise characteristics are not important for your subtraction e For Pupil Tracking mode to peform S ADI you should consider whether your primary and companion objects both fit within the 0 8 x0 8 FOV of the 25 mas scale or whether the 100 mas scale with 3 x3 can be used but with sub Nyquist sampling You should also ensure that there should be enough field rotation to minimise self subtraction of the companion signal The primary source should not exceed the persistence levels for the detector and the secondary should be faint enough in the optical bands e g R compared with the primary such that it will not affect the AO performance this means a difference of gt 3 8 magnitudes If the companion position is known you should ensure it remains withi
98. n the FOV during the exposure sequence especially if the primary is not placed at the centre of the FOV Furthermore pay attention to the instrument orientation and the expected trajectory of the secondary in the FOV Given the spaxels are not square but rectangular it may be easier to resolve the companion if it is placed at 12 o clock or 6 o clock of the FOV 4 2 SINFONI specifics to templates OBs and p2pp SINFONI follows very closely the philosophy set by the ISAAC short wavelength and NACO templates It is simplified by the fact that SINFONI offers only one mode of observing IFS Integral Field Spectroscopy 4 2 1 Templates For detailed descriptions of the templates please see Sec 12 Only a rough outline of the templates is given below Acquisition Acquisition templates allow one to distinguish between the cases of observing with out AO _acq noA0 and with an AO Guide Star NGS or LGS for AO corrections acq NGS _acq_LGS SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 20 There are two particularities of the noAO acquisition templates e lt allows to flag whether the Deformable Mirror DM should be flattened after the telescope preset before the observations this is mandatory to obtain the best image quality e t allows an end offset to be made i e to acquire a bright star and perform a known offset to the real target The acquisition for AO also has a few particulariti
99. natural guide star acquisition IFS with nodding to selected sky field s SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 58 It should in most cases be possible to prepare the science OBs with a combination of these 7 recommended templates You may need the other templates in the case that special night time standards or calibrations are requested Night time arcs and flats are typically not needed even though they are offered for the time being The usual rules for OBs apply you can include only 1 acquisition template it can be followed by several science templates changes to set up are possible between the science templates offsets of more than typically a few arcminutes will imply the re acquisition of the telescope guide star i e produce a large overhead As of P87 Phase 2 the new template SINFONI_ifs_cal_GenericOffset has been added to allow effi cient observations of a PSF calibration star in LGS noT TS mode this template is basically a clone of template SINFONI_ifs_obs_GenericOffset but allows user defined offsets to a suitable PSF cali bration star beyond the range of the field selector Template SINFONI ifs cal GenericOffset can only be used in LGS noTTS mode As of P93 a new Pupil Tracking mode has been implemented for NGS observations This is enabled by setting the PUPILTRK keyword to TRUE in the SINFONI_ifs_acq_NGS and SIN FONI_ifs_acq_NGSfast acquisition templates The latter should be used for
100. nce observations The SINFONI ETC can be found at http www eso org observing etc 2 1 Reference source for wavefront sensing For SINFONI NGS or LGS the curvature wavefront sensing occurs at optical wavelengths lt 1um with avalanche photo diodes APDs which show a high photon response over a very broad wavelength range A natural AO guide star NGS should ideally be bright close and compact We will present in this section a brief overview on what can be done with the available AO guide star for the user selected science targets Please note that there is no perfect correlation between seeing NGS parameters brightness dis tance and the Strehl ratio of the obtained data The coherence times and isoplanatic angles may be distributed over a relatively wide range for a given atmospheric optical seeing value FWHM and spectral range J H or K The distance of the AO guide star Two identical field selectors FS one for NGS the other for LGS allow to pick the AO guide star within a 2 x1 field centered on the spectrograph field Note that the vertical axis of the FS field of view is rotated by 25 deg i e the Y axis is positioned 25 deg clockwise from East see Fig 1 A check has been introduced in P2PP to inform the user in case the selected reference star is located outside the range of the FS or if the sequence of offsets bring the FS beyond its mechanical limit However it is important to note that the AO
101. nce there is no conclusion about how the spectra of the off axis periscopic sky spiders can be matched with the on axis target field The option has been left selectable for further test observations only Spectral dither allows to increase the sampling of the spectra in dispersion direction If this parameter is selected then the grating is rotated to move the spectra by half a SPAXEL equivalent to 1 pixel in dispersion direction If selected exposures with both dithered wavelength settings are taken for any object and sky position and for any calibration frame taken at day or night time The spectral dithering is only supported for visitor mode observations Pupil Tracking This is handled by the acquisition template 12 2 1 SINFONIL ifs obs FixedSkyOffset The template moves the telescope alternatively between object and sky positions nodding The object positions are randomly distributed jittered around the object initial telescope position and within a box whose dimensions are set by the parameter Jitter box width in arcsec The size of the jitter box should be typically between 4 and 32 times the selected SPAXEL size The sky positions are also randomly distributed around a fixed offset position defined by the parameters Alpha offset to sky and Delta offset to sky from the original target telescope position The box dimension of the random sky positions are also set by the parameter Jitter box width around t
102. ng a single observation re turning a completed FITS file to the SOS e ASM Atmospherical Site Monitor The ASM is used to retrieve the current atmospheric parameters for use in compensating for transversal atmospheric dispersion e VOLAC VLT Online Archive Client VOLAC implements the interface to the VLT archive system by which clients can request the archival of science product 55 Part Ill Reference Material 11 The SINFONI science calibration plan The calibration plan defines the default calibrations obtained and archived by the Paranal Science Operations without being explicitely requested by the service or visitor mode users We provide here a brief overview 11 1 The science calibrations in a nutshell SINFONI calibration plan Calibration of exposures frequency purpose Dark 3 daily to create master dark frame bad pixel map Wavelength calibration 1 on off pair daily to compute wavelength calibration Lamp flat field 5 on off pairs daily to determine pixel to pixel variations and large scale illumination Twilight flat field twilight flat fields are not possible Telluric standard 1 observation daily to remove telluric features from the science exposures The Telluric will be taken within 2 hours of the science observations with an airmass tolerance of 0 2 Detector characteristics gt 10 on off monthly series of flat fields with increasing intensity to determine read out noise gain detector
103. not the science target itself and usually closer than 10 Depending on the atmospheric conditions atmospheric coherence time and isoplanatic angle the AO guide star could be chosen as far as 30 for the AO system to still provide a mild improvement of the encircled energy Since Period 79 SINFONI has been operating with the Laser Guide Star LGS The system provides Strehl ratio in the 10 2096 range under excellent conditions Tip Tilt Stars TTS as faint as R lt 17 can be used with a maximal separation of 1 arcmin from the science target A new LGS mode with no TTS the so called Seeing Enhancer mode or SE mode has been available since Period 84 LGS requires CLEAR sky and airmass lt 1 5 Please note that the LGS mode resp NGS mode so far does not support differential tracking between the Tip Tilt Star resp NGS star and the science target From Period 93 onwards a new Pupil Tracking mode is offered for the NGS mode enabling the use of the Spectral Angular Differential Imaging S ADI technique to obtain simultaneous imaging spectroscopy of faint companion sources around K gt 5 mag sources SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 This page was intentionally left almost blank V SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 Contents 1 Introduction Lt Deupeer thisdocument iux EGRE SHAG SRE RARE RE CE DS ei L2 Structure OF this document uuu dev ww eX eee 3v X ee omo a L
104. ns 5 Observing with SINFONI at the VLT hl AVSIM orem bee Xodee ES GE NP SEEDS OES Eee A OE 5 2 Visitor Mode Operations us lt 6 42024 eae as WON HB HH Fe O wO o o co Jl OD 4 4 R op RO SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 53 The influence of the Moon 4 626868 682 25 2a sas 54A Weatherconstraints uu ous xy ohm ey ou devoto we bee be 4 X0 wale 3 55 Target AGQUISIDION lt lt uoo oe ox oder AA 3 E xou Ro a 5 6 Measuring the Strehl ratios reference PSF stars 5 7 rnentalion CONVENCI N lt lt lt essere a 5 8 Offset conventions and definitions 02 00 eee ee ee 5 9 Instrument and telescope overheads o oo a a a a The SINFONI data reduction pipeline 6 1 Required Input Frames for the Pipeline aa a 020000 56 11 R f rence Files uuo uum LEN a a A Gla Raw fames 2023214 ee A ten ee erg gx 61 3 Calibration Prod cts A ss saec oe eine eee OR 3 52 Data Reduction Steps o sc 245456482805 de a ERE OE 6 2 1 Detector Linearity and Bad Pixel Mask Determination 6 2 2 Bad Pixel mask and Master Dark Determination 6 2 3 Master Spatial Flat and bad pixel determination 6 2 4 Detector s distortion and slitlet distances determination 6 2 5 Wavelength solution determination 6 2 6 Standard star data reduction 27 PSE Gate red ction noce ne Shee bade a eee wd od a O25 Science observation
105. nstruments sinfoni doc VLT MAN ESO 14700 4037 pdf for details Since the instrument is likely to change over time you should also consult the SINFONI Data Processing and Quality Control page where the time evolution of many of the parameters are available as well as detailed explanation of each of the parameters http www eso org observing dfo quality index_sinfoni html 6 1 Required Input Frames for the Pipeline 6 1 1 Reference Files Reference Bad Pixel Map The reference bad pixelmap marks the first and last four rows and columns of the detector as bad This map must be combined with the other bad pixel maps created by recipes si_rec_detlin and si_rec_bpmap to generate a master bad pixel map Line Reference Table For distortion determination and wavelength calibration it is necessary to include a reference line table REF_LINE_ARC These are arc lamp and OH emission line lists vacuum wavelength and relative intensities obtained from the National Institute for Standard and Technology physical reference data or literature Reference line lists should contain only those lines found within the band in question First column of first slitlet If frame stacking is required a FITS table FIRST_COL giving the first column of the first slitlet for each spectral band and pre optics is necessary This value is assumed to be zero 6 1 2 Raw frames Dark Frames Produced by SINFONI_ifs_cal_Darks Dark frames with exposure times
106. of companions around K gt 5 mag sources Since P92 SINFONI has been operating with the new solid state laser PARLA with on sky power of 7 W PARLA is available to SINFONI every night Since P84 SINFONI has been offered with a new LGS mode named Seeing Enhancer SE mode which will not require a TTS only the high orders of aberration are corrected but no tip tilt The SE mode provides some improvement with respect to the seeing limited no AO mode but only under very good conditions Therefore the SE mode requires seeing constraints of 0 8 or better Since P81 the use of the fast acquisition template is offered in service mode but a waiver needs to be submitted to the User Support Department at the time of preparation of the Phase 2 OBs see http www eso org sci observing phase2 SMGuidelines html for additional infor mation Since P78 Paranal s Rapid Response Mode RRM is offered for SINFONI too please see http www eso org sci observing phase2 RRMObservation html for more information about the RRM mode The Rapid Response Mode is offered for observations of transient phenomena such as gamma ray bursts or supernovae in semi automatic mode The user PI or Co l of an approved target of opportunity program submits an ftp file with the coordinates of the target to SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 2 a specific ftp server on Paranal A special program at the telescope continuous
107. ond turning process The mirrors are gold coated for higher reflectivity 9 4 Grating wheel In total SPIFFI has four gratings to cover the J H and K atmospheric windows and the combined H amp K band The gratings are directly ruled in gold on an Aluminium substrate and every grating is blazed to the centre of its passband In order to be able to move the spectrum on the detector with an accuracy of 1 5 of a pixel the grating wheel is driven with a 1 647 gear and controlled via an inductive encoder directly attached to the grating wheel SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 51 Figure 20 SPIFFI image slicer a The light enters through the hole in the big slicer A stack of 32 small mirrors the small slicer also shown in the sub panel slices the image and redirects the light towards the 32 mirrors of the big slicer which re arranges the slitlets into a 31 cm long pseudo slit 32 1 47 148 49 20 21 22 23 24 BLU i4 r3 2 22 23 24 9 7 407 4474 77437 447457746 77317730 7 29 7 287 27 7 26 77 2577 Figure 21 The layout of the slitlets on a raw SPIFFI frame grating parameters setup Ae range J 1 25um 1 10 1 40um H 1 65um 1 45 1 85um K 2 20um 1 95 2 45um H K 1 95um 1 45 2 45um 9 5 Spectrometer camera SPIFFI is equipped with a Rockwell 2kx2k pixel Hawaii 2RG array and a lens spectrometer camera built by a NOVA MPE ESO consortium The camera is a five lens 1 folding
108. ontrol Software LGSF Laser Guide Star Facility MACAO MACAO AO System SPIFFI Instrument and its RTD ASM Atmospherical Site Monitor VOLAC VLT Online Archive Client In normal operation MACAO is coordinated by the SINFONI SOS driven from templates scheduled by BOB or from the SOS GUI however a stand alone mode of operation is also provided for AIT in which MACAO can be operated without SPIFFI or the SINFONI SOS The SOS performs the set up of all of the sub systems required for a particular SINFONI exposure depending upon the instrument mode starts the exposure and monitors the status of the exposure finally archiving the science data using VOLAC TCS Telescope Control Software The TCS provides the interface by which MACAO can off load high stroke Tip Tilt and Focus errors to the telescope In normal operation all communication with the TCS is via the SOS SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 54 e LGSF Laser Guide Star Facility The LGSF controls the laser generation and up link allowing the SOS to request a laser spot to be projected at a particular location A fast Tip Tilt signal is fed directly from MACAO to the LGSF to control laser jitter The LGSF provides the information required for the initial setting of the differential focus trombone and may be the source of the focus offset used to control the focus trombone during observation e SPIFFI The SPIFFI instrument S W is responsible for performi
109. oposal form SINFONI can be used with and without AO guide star Your target list will not be checked for valid AO guide stars as it is done e g for NACO SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 17 Your choices of set ups are given below You are requested to tell us whether you will or will not use the AO Note that we decided that it would make no sense to work with the 25 mas plate scale if you are not using adaptive optics ANINSconfig HSINFONIHPRE IMGHprovide HERE list of setting s J H K H K INSconfig SINFONI IFS 250mas pix no AO provide HERE list of setting s J H K H K INSconfig SINFONI IFS 100mas pix no AO provide HERE list of setting s J H K H K If you plan to use a NGS please specify the NGS name and magnitude Rmag preferred otherwise Vmag in target list INSconfig SINFONI IFS 250mas pix NGS provide HERE list of setting s J H K H K INSconfig SINFONI IFS 100mas pix NGS provide HERE list of setting s J H K H K INSconfig SINFONI IFS 25mas pix NGS provide HERE list of setting s J H K H K If you plan to use the LGS please specify the TTS name and magnitude Rmag preferred 4 otherwise Vmag in target list ANINSconfig H SINFONIHIFS 250mas pix LGS provide HERE list of setting s J H K H K ANINSconfig H SINFONIHIFS 100mas pix LGS provide HERE list of setting s J H K H K ANINSconfig H SINFONIHIFS 25mas pix LGS provide HERE list of
110. ould be insignificant compared to the primary a back of envelope calculation suggests that Amp should be larger than 3 8 mag Asking in the README for the diameter of the entrance diaphragm of the MACAO system to be manually reduced may also help to block out the light from the companion e Pupil tracking is only offered in NGS mode it is not available for LGS or noAO e There will be no pipeline support for the mode however the existing pipeline can be used to output individual data cubes by suitable choice of parameters SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 15 A Phase 1 applying for observing time with SINFONI This section will help you to decide whether SINFONI is the right instrument for your scientific project take you through a quick evaluation of the observing time needed and guide you through the particularities of SINFONI in the proposal form 3 1 Is SINFONI the right instrument for your project 3 1 1 The AO guide star In order to use the AO module in NGS mode your target should be close lt 10 to a bright R lt 14 mag guide star or should be suitable as a guide star itself Under these conditions the diffraction limit of the telescope can be approached or achieved Stars brighter than R 11 mag are dimmed using neutral density filters in order not to blind the APDs of the wave front sensor Fainter guide stars can be used but the performance of the AO module degrades rapidly with fainte
111. panions SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 10 PSF center stability as f ParAngle for HIP69845 Cubes 1 4 PSF stability 2 03 2 04um PSF stability 2 10 2 12um as T T T T 35 T T T T F 38 L Aar 34 e L 9 i d o v i sa 9 e g e v ParAngled ZA m d g g S Y E F s e o o gt 32 32 e E o o o9 18 E F AA liisis al AA L ren at A abusa al eet 34 35 38 37 34 35 38 37 PSF X center PSF X center PSF stability 2 10 2 42um PSF stability 2 38 2 41um LE ME E 35 J asl E i L 34 7 at 7 P e o o o gt o o 9 o o i ARS S b AUS e gt e gt ge 1 sat N ge t o 3 4 q e a ee a o Y o o e 2 L e 7 oe Eis e o 1 32L e ef 4 E e e i L L A L L 1 1 1 LA 34 35 37 34 35 37 PSF X center PSF X center Figure 3 PSF drift over the course of 1 3 hours as a function of position in the FOV in units of 0 0125 2 9 1 Expected performance Early performance estimation is based on pupil tracking observations of a K 7 8 mag B9V star with no companion with artificial companion signals injected into the data and then analysed using standard 2 D ADI reduction techniques The observations were centred around meridian transit with a total elapsed time of 1 3 hours including acquisition and a total field rotation of 57 and airmass of 1 0 The observations were done with the 25 mas scale and K band The ambient condi
112. performance will strongly degrade for AO guide stars at distances greater than 10 to 15 seconds depending on the selected wavelength band J H or K Under excellent conditions bright stars as far as 20 30 can still be used to provide a mild improvement of the image quality The brightness of the AO guide star The intra and extra focal pupil of the AO guide star is imaged on a lenslet array and each lenslet fed to an Avalanche Photo Diode APD that ultimately forwards its signal to the Real Time Computer RTC The flux on the APD is limited to 1 million counts in order not to damage the devices and thus stars brighter than R 11 mag are dimmed by a set of neutral density filters for up to 9 mag Hence stars brighter than R 2 mag cannot be used as AO guide star Stars brighter than R 11 mag will not improve further the performance of the AO system Note also the detector persistence SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 5 30 30 Figure 1 Orientation and size of the Field Selector field of view limit of SPIFFI effectively limits the source magnitude to K gt 6 7 mag if the AO guide star is also the science target Good correction under average seeing is still obtained with stars as faint as R 14 mag Any fainter guide star will then require very good or excellent atmospheric conditions to obtain diffraction limited images Partial correction maybe obtained down to R 17 magnitudes
113. primary spectral energy using a high pass filter An anisotropic PSF was also convolved After recentering a master PSF was made and it was subtracted off the individual cubes Finally the individual frames were re rotated re normalised and median combined The artificial secondary was injected into the data covering a range of distances from the primary with varying polar angles Different fluxes for the secondary were tested 100 10 1 and 0 5 AUDs with the primary peak flux at 1300 ADUs Fig 4 shows the results of the processed data At Amr 7 8 it is still possible to detect the secondary at about 3 6 A D 0 17 0 29 from the primary Fig 5 shows the 5 c theoretical contrast curve without secondary injection as a function of distance A D while Fig 6 shows the expected 5 sigma contrast of SINFONI compared with other example contrast curves showing that medium contrasts between 6 and 8 5 magnitudes at 5 c significance can be expected at distances between 0 17 and 0 29 for the 25 mas scale Note that the above utilised standard 2 D ADI techniques but it is also possible to combine this with Spectroscopic Differential Imaging SDI techniques e g Thatte et al 2007 where the PSF is obtained and subtracted off by scaling the PSF of adjacent wavelength slices Thus further gains in sensitivity may be possible 2 9 2 Important considerations Before deciding whether Pupil tracking is suitable for your program the
114. r magnitudes Under excellent conditions guide stars with R 17 mag have been used providing a mild improvement of the image quality Guide stars as far as 30 can also be used under very good conditions but again the patch of the atmosphere that will be corrected will not be the one located in front of your target i e the image quality improvement on target will not be optimal Guide stars further away than 30 are generally not useful Seeing limited observations If no AO guide star is available or needed the deformable mirror is flattened using the calibration fibre during the target acquisition and the AO module just acts as relay optics with 5 warm reflections The shape of the deformable mirror has to be recalculated as soon as the telescope altitude airmass or paralactic angle has changed significantly typically by more than 0 1 in airmass since the flattening LGS observations Please refer to the information in Section 2 2 for LGS progams 3 1 2 Limiting magnitudes Limiting magnitudes S N 5 per spectral pixel point sources integrated over the typical size of the PSF in 1h integration on source are Field of View Scale mode Limiting Magnitudes continuum 8 x 8 250mas noAO J 20 2 H 19 9 K 17 9 H K 19 6 Ke 100mas NGS J 19 4 H 19 6 K 18 8 H K 19 8 0 8 x 0 8 25mas NGS J 17 8 H 18 7 K 18 3 H K 19 2 We have selected a seeing at visual wavelength of 0 8 which would be equivalent to infra
115. rame the closest sky frame in time is selected and the pair is stacked Objnod step is executed on the stacked frames generating wavelength calibrated data cubes The resulting cubes are averaged together weighting by the integration times A mask cube is produced containing the total integration time on each pixel of the result cube Additionally OH sky emission lines can be used to track and correct the instrumental flexure ER Part Il SINFONI a detailed description of the instrument 7 General description 7 1 Observing with Adaptive Optics The following section describes some basics on adaptive optics and atmospheric turbulences es sentially taken from the NACO user manual Interested users could extend on the subject starting e g with Adaptive optics in astronomy Rodier 1999 Cambridge University Press or Introduc tion to adaptive optics Tyson 2000 Bellingham SPIE 7 1 1 Atmospheric turbulence The VLT has a diffraction limited resolution of A D 0 057 arcsec at A 2 2um But the resolution is severely limited by atmospheric turbulence to A ro 1 arcsec where ro is the Fried parameter It is directly linked to the strength of the turbulence and depends on the wavelength as AHIR For average observing conditions ro is typically 60cm at 2 2 jum Temperature inhomogeneities in the atmosphere induce temporal and spatial fluctuations in the air refractive index and therefore cause fluctuations in the optical path
116. rection will be strongly degraded with increasing distance of the TTS from the science target and with decreasing brightness of the TTS By comparison with the case of an on axis NGS star under median seeing conditions for Paranal the achieved Strehl ratio will be degraded by a factor of two for a TTS that is 40 from the science target It is also important to remember that due to the Cone Effect the maximum Strehl achievable with the LGS is significantly less than the one obtained with a bright NGS The SINFONI ETC includes observations with the LGS mode see http www eso org observing etc One can expect the laser to create an artificial star whose magnitude will be V 12 13 mag The TTS must be a single star and not a binary there should not be a star with similar brightness within 3 distance failure to do so will likely cause a failure in the AO loop The user should advice in the README if crowding can be a problem for the TTS LGS observations are only possible for airmass lt 1 5 Users should set the maximum airmass in their OBs to lt 1 5 In summary you must make sure that you have a TTS within a distance of 1 arcmin maximum from your science target which must be a single star You should clearly state why you need to use this mode and include the characteristics of the TTS V or R band magnitude RA DEC and spectral type if known LGS observations can only be carried out under clear sky conditions no cirrus or any
117. red seeing values of 0 67 0 63 0 59 and 0 61 for the central wavelength of the J H K and H K spectral ranges respectively For closed loop AO with natural guide star NGS we have assumed a NGS at a distance of 10 and photometric brightness of R 12 and B R 1 5 magnitudes For more detailed exposure time calculation please use the exposure time calculator SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 16 3 2 The Exposure Time Calculator ETC The SINFONI Exposure Time Calculator ETC can be found at http www eso org observing etc It returns a good estimation of the integration time on source needed to achieve a given S N as a function of atmospheric conditions A few words to the various input parameters also read the online help provided on the ETC page e the parameters to be provided for the input target are standard The input magnitude can be specified for a point source for an extended source in which case we compute an integration over the surface defined by the input diameter or as surface brightness in which case we compute values per square spaxel e g 100x100 mas e if an AO guide star is used do not forget to tick the box AO under instrument set up and provide the values for AO guide star distance its R mag and B R color The two latter can be obtained from many of the online star catalogs e g GSC Il USNO UCAC and are used to compute how much photons will be available to
118. rs Since the hidden parameters will be rarely changed during science observation runs we do not provide an explanation here in the template reference section Unlike for other instruments there are only a few templates available for SINFONI There exists only the integral field spectroscopy IFS observation mode You will find below the list of templates together with the short description of the functionalities SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 57 acquisition templates functionality comment SINFONI ifs acq NGS interactive Natural Guide Star ac recommended quisition SINFONI ifs acq NGSrrm interactive Natural Guide Star ac recommended SINFONI ifs acq NGSfast quisition in RRM mode fast Natural Guide Star acquisition for bright targets only SINFONI_ifs_acq_LGS LGS and or TTS acquisition recommended SINFONI_isf_acq_noAO open loop acquisition recommended SINFONI_isf_acq_noAOrrm open loop acquisition in RRM mode recommended science templates SINFONI_ifs_obs_FixedSkyOffset IFS with jitter and nodding fixed recommended sky SINFONI ifs obs GenericOffset IFS with user defined offsets recommended SINFONL ifs obs AutoJitterSpider SINFONIL ifs obs AutoJitter IFS with jitter and sky spider IFS with jitter only no sky offsets not supported night time calibration templates SINFONL ifs cal StandardStar SINFONL ifs cal PSF SINFONL ifs cal NGS SINFONL ifs cal Generic
119. rument setup The SIN FONI spatial elements spaxels on the sky are not square twice as tall as width but rectangular The FOV is divided into 64 elements pixels in the x direction and 32 elements slices in the y direction The Spaxel size is the height of one of the 32 image slices on the sky which can be 0 025 0 1 or 0 25 arcsecs depending on the chosen preoptics Each image slice is projected onto 64 pixels on the detector by the SINFONI collimator and camera optics so that the final spatial element measures 1 Spaxel size in y and 0 5 Spaxel size in x The instrument setup name is a symbolic name for the setup required to center the J H K and H K spectra on the detector The respective setups include the selection of the grating grating angle spectral order and order sorting filters The SkySpider Position should be left in the ref erence position since there is uncertain how the spectra of the off axis periscopic sky spiders can be matched with the on axis target field The option has been left selectable although the SkySpider option has never been commissioned Figure 24 An illustration of PA definition and spatial sampling In this example a target binary system with the axis at PA 20 is observed The left plot shows the FOV with the instrument position angle on sky set to 0 The finest sampling will be along the E W direction On the right plot the instrument position angle on sky is set to 70 The bin
120. s A ooo ox ESSE dde SINFONI a detailed description of the instrument General description 7 1 Observing with Adaptive Optics e GALL Atmospheric turbulence 2 A ee Oe ewe eae Xs 7 1 2 Adaptive Optics 2 noo moe oe AR AR RS L2 The Laser Guide Star mode 2 24642 sow oso E oho 94 44444 7 2 1 Background information on LGS lll ls 7 242 LGS mode at Paranal UT4 su 7 3 Observing in the Near Infrared 1 3 1 Atmospheric Transmission lt lt lt lt lt s Pas Bagkground EMISSION ici da eres 7 3 3 Spectrophotometric Calibration ls 7 4 Integral Field Spectroscopy sk o EE RE xx The Adaptive Optics Module 8 1 AO Module System Description 8 1 1 The AO Adapter circa 2a OS PS wae XOU AA oes vil SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 viii 81 2 The Main nuuwee com3eeX eR SEES CERES x 40 Blo The errective Optics usus doy ed eee a eee er 3 41 81 4 The Wavefront Sensor coses o o og oo ee 42 8 1 5 LGS mode elements 0 oss ERR xU a 43 815 Calibration UNI s s eroa rad sa BAS ERROR ERE SEER RS 45 8 2 AO module System Performances 46 8 2 1 NGS performances EE Rm g e a RR 46 8 2 2 LGS performances inicia asa a A 47 9 The integral field spectrograph SPIFFI 49 o ok ee EIN 49 Q2 Image Sheek AE E NN 49 9 3 Spectrometer collimator 2 2 4 bee te bee GROS 49 9 4 Grating wheel IN ow Sw GAR ee a RE O
121. s to an uncertainty of 5 20 in the absolute flux calibration If users wish to have a more certain absolute flux calibration they should provide their own standards and should have included these observations in their requested time in Phase 1 Alternatively if the broad band magnitudes of the object are known the absolute flux calibration can be derived by convolving the measured spectrum with the broad band filter curves In this case the IR magnitude of the standard is irrelevant only the spectral type is important 7 4 Integral Field Spectroscopy The basic design of any Integral Field Unit IFU is a unit which splits the field of view into individual spatial elements spaxels and recombines them into pseudo longslit s which are then passed through a standard spectrometer The SPIFFI IFU is an image slicing design which uses a series of mirrors to slice the field of view into 32 sections which make a single pseudo longslit Fig 10 Each slice is imaged on 64 detector pixels Thus this design provides a square grid of 32x64 rectangular spaxels each 1 2x1 the slice width Two dimensional original on sky image Optical slicing of the on sky image NES aw S Spectral dipersion of the sliced image Wavelengths Computer reconstruction of the 3D data cube Spectrum of each 2D pixel a Spatial in Y e S A Spatial in X 9 Computer reconstructed image Figure 10 The function of the image slicer The f
122. s with polynomial coefficients deviating more than a user defined factor from the mean are flagged bad 6 2 2 Bad Pixel mask and Master Dark Determination Recipe sinfo_rec_mdark Purpose 1 bad pixel mask generation SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 31 Frames are stacked and on each pixel the standard deviation of intensity is computed The clean mean of those values is calculated The pixels which deviate more than a user defined factor times the standard deviation from the clean mean are flagged bad Purpose 2 Master Dark s creation Input frames with same DIT are stacked together and clean mean is computed for each stack 6 2 3 Master Spatial Flat and bad pixel determination Recipe sinfo_rec_mflat Purpose Generates a master flat field Clean mean is computed for both on and off frames and off frame is subtracted Bad pixels are interpolated and the intensity of the master flat is normalized Additionally a bad pixel map can be generated Pixels which deviate more than a user given factor from their neighbourhood are flagged bad Furthermore clusters of bad pixels can be detected 6 2 4 Detector s distortion and slitlet distances determination Recipe sinfo_rec_distortion Purpose 1 detector s distortion determination Fiber frames are stacked with different rejection thresholds to determine a fake slitlets on and a fake slitlets off frame Fake off is subtracted from fake on frame LAMP_FLAT
123. setting s J H K H K If you plan to use the LGS without TTS seeing enhancer mode then please leave the TTS name blank in the target list ANINSconfig H SINFONIHIFS 250mas pix LGS noTTS provide HERE list of setting s J H K H K ANINSconfig H SINFONIHIFS 100mas pix LGS noTTS provide HERE list of setting s J H K H K ANINSconfig HSINFONIHMIFS 25mas pix LGS noTTS provide HERE list of setting s J H K H K If you plan to use the Pupil Tracking mode 4 INSconfig SINFONI Pupil Track Select if you need pupil tracking mode If you have special or non standard calibrations 4 INSconfig SINFONI Special Cal Select if you have special calibrations If you will use the Rapid Response Mode 7 INSconfig SINFONI RRM yes SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 18 4 Phase 2 Preparing your SINFONI observations This section provides a guide for the observation preparation for SINFONI during Phase 2 both for Service Mode and Visitor Mode We assume that you are familiar with the generic guidelines which can be found at e http ww eso org sci observing index html Proposal preparations e http www eso org sci observing phase2 Phase 2 preparations http www eso org sci observing phase2 P2PP P2PPTool html OBs preparations e http www eso org sci observing phase2 SMGuidelines html Service Mode e http www eso org sci observing phase2 VMGuidelines html Visitor Mode e
124. sf NODEFAULT Instrument setup name Hidden parameters DPR CATG CALIB CALIB Data product category DPR TECH IFU IFU Data product technique DPR TYPE WAVE LAMP WAVE LAMP Data product type SINFONI_ifs_cal_LampFlats Lamp Flats day time calibration Parameters to be specified Parameter Range Default P2PP Label DET DIT 0 3600 NODEFAULT Integration time DIT DET NDIT isf NODEFAULT Number of Integrations NDIT SEQ NEXPO 1 1000 1 Number of exposures per offset position SEQ SPECDITH TE F Spectral dithering INS LAMP5 VALUE 0 127 NODEFAULT Halogen lamp value 0 127 INS MIRR1 NAME isf Ref SkySpider Position INS OPTI NAME isf NODEFAULT SPAXEL size arcsec INS SETUP NAME isf NODEFAULT Instrument setup name Hidden parameters DPR CATG CALIB CALIB Data product category DPR TECH IFU IFU Data product technique DPR TYPE WAVE LAMP FLAT LAMP Data product type SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 SINFONI_ifs_cal_Darks Darks calibration Parameters to be specified Parameter Range Default P2PP Label DET DIT isf NODEFAULT Integration time DIT DET NDIT isf NODEFAULT Number of Integrations NDIT DET NDITSKIP isf NODEFAULT NDIT to skip DET NDSAMPLES isf NODEFAULT Number of samples DET NDSKIP isf NODEFAULT Samples skipped per NDIT SEQ NEXPO 1 1000 1 Number of exposures per offset position Hidden parameters none DPR CATG CALIB CALIB Data produc
125. so AutoJitterOffset tem plate is not offered anymore Issue 78 3 2006 06 25 cover amp text Small changes mostly typos and en glish were corrected Issue 79 1 2006 09 09 entire doc Fixed some small inconsistencies wrt Period 79 Issue 79 2 2006 11 27 entire doc Fixed some small inconsistencies throughout the text wrt grating wavelength range Issue 80 1 2007 02 17 entire doc Update for P80 Phase 1 Issue 80 2 2007 02 23 5 amp 12 Added availability of fast acquisition template in service mode waiver re quired Issue 80 3 2007 05 25 all sections Small changes for preparation of P80 Phase 2 LGS infos updated Issue 80 4 2007 06 13 2 1 2 2 12 2 3 Added infos about field selector orienta tion and offsets in auto_jitter template Issue 81 1 2007 08 26 1 3 2 1 5 7 8 2 2 12 1 Some small updates for CfP81 Issue 81 2 2007 09 06 2 1 Orientation of Field Selector updated Issue 81 3 2007 09 10 2 1 2 2 8 2 2 Updated magnitude limits of TTS for LGS obs Issue 81 4 2007 12 04 12 2 Update for P81 Phase 2 keyword change in auto_jitter template Issue 81 5 2007 12 05 12 2 2 Corrected sign error in caption of fig ure related to generic_offset sequence in SKY mode Issue 82 1 2008 02 28 1 3 2 2 3 3 7 2 12 0 Offering LGS without TTS SE mode on a best effort basis for P82 Issue 82 2 2008 05 28 5 6 12 2 Explanation of PA convention and re turn to origin
126. ssembly There are two sources of contamination of STRAP by the reflected laser light 1 on axis the LGS itself produces locally a background which can be in worst case conditions as bright as 700 times the sky background seen by STRAP in dark conditions when pointing to zenith 2 off axis the Rayleigh scattering by lower atmospheric layers produces a bright annulus in the focal plane Its maximum surface brightness can reach 1000 times the dark sky background seen by STRAP as shown on in Fig 16 Since STRAP works in the photon noise regime it is essential to filter out the laser light background in order to maximize the limiting magnitude of STRAP and hence the sky coverage This is achieved SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 45 by means of a notch filter located in front of the STRAP head blocking the 589nm light and dimming the laser background below the dark sky brightness In addition a second filter wheel selects the appropriate Neutral Density Filter in order to reduce the APD number of counts to within their linear range when observing a bright star 1200 2 0deg z 20deg LGS rayleigh Sky background 0 10 20 30 40 50 60 off axis disntace arcsec Figure 16 STRAP unit STRAP assembly 8 1 6 Calibration Unit The Linear Unit Focal plane is used to insert different calibration sources into the optical path It consists of an X Y Z table 3 linear translators which prov
127. t category DPR TECH IMAGE IMAGE Data product technique DPR TYPE DARK DARK Data product type 76 SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 77 13 The Spectral Resolution of SINFONI In this section we summarize the preliminary measurements of the spectral resolution of SINFONI Here we refer only to the PSF in spectral direction The spectral resolution of SINFONI is com plicated by the fact that the various pre optics illuminate the gratings differently This causes a strong dependence of the spectral resolution on the selected pre optics Below we show spectral PSFs as measured during the SINFONI commissioning courtesy A Gilbert from MPE for all plate scales in all bands The profiles were smoothed from super sampled arc lines wavelength calibrated and collapsed in the spatial direction The spectral resolutions per band and plate scale when simply computed from the FWHM of the arc lines are Spectral Resolution Spatial Scale Band 250mas 100mas 25mas J 1870 1800 2360 H 2920 2730 5500 K 4490 5090 5950 H K 1640 2050 2710 Note however that this does not take into account that the lines are not Nyquist sampled in all modes The averaged FWHM in pixels is Resolution in Pixels Band 250 100 25mas J 447 464 3 53 H 2 83 3 02 1 50 K 196 1 73 1 48 H K 2 37 1 90 1 44 Thus for the cases in which the FWHM is less than 2 pixels the spectral resolution is probably to be compu
128. t the readout to be about once every 1 to 2 minutes However the current overheads are rather large for short DITs with an efficiency of 35 60 For example with DIT 3 and NDIT 15 the total duty cycle time is 125 seconds yielding a 36 efficiency only while with DIT 20 and NDIT 2 the total duty cycle time is 68 seconds yielding a 59 efficiency e Note also that for bright objects with K lt 6 mag the SINFONI_ifs_acq_NGSfast acquisition template should be used since it skips the 250mas and 100mas scales during the acquisition to avoid causing persistence to the detector e For the science observations one would normally expect to use the SINFONI_ifs_obs_GenericOffset template setting the offsets to be zero or to a small value if a tiny sub pixel offset is desired but at the expense of increased overheads Note normally one would set the observation type to Object and the number of offset positions to a fairly large number to cover the duration of the meridian transit SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 14 e For observations centering around meridian transit it is mandatory to append _MERIDIAN to the OB name e The primary and the companion should not be of comparable brightness in the R band otherwise the wavefront sensing may be affected resulting in an elongated PSF The field may also rotate around the centre of mass of the binary The brightness of the secondary sh
129. ted from a resolution of 2 pixels dispersion being 0 15 0 2 0 25 0 50 nm pix for the J H K H K bands respectively SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 78 aset aset ess veer str aset oer weer Gase T cse SISET orseT amer weer T STET T wez T LLLLE lal Uad az LLL O08 T T auser T aset T SIScT T B S g B B E VET TEEREEET TET EET TET 3 3 TT SITT eE oer oer ouer T aerer S8PrT vert T vert T aert T aert DEN KS 8 8 Os pm L OLTZT OSTZT ouer T vert oer T T oer T Br EEE E va i LLLI LLLI LL S S S 8 aset oct 00821 T T _ SISET T 8 3 3 s s s 3 ee 9 vert aert aert aert veer oer oer SOIZT c OSTZT SLOTT gent Serr SOST T SBOT T van T T gett T gert T vert T aert T Mm Nn em zi D Lei T D SC 2 A S E 5 B CH a O Eh CH Lei Mm N z D Lei Figure 28 Spectral point spread function in the J band For the three different plate scales for three regions on the detector top to top top to bottom on detector SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 79 SZ6LT eet ST6L T tett L eet SE6L T SI6LT OZ6L T SZ6L T geet Se6L T
130. the lamps on and the other with the lamps off Note that the LampFlatAtt and ArcAtt templates can only be used as the last templates of the OB without losing the AO reference star We do not expect that arc lines calibrations will be needed at night time since there a many OH lines in the IR sky which can be nicely used to calibrate medium resolution IR spectra SINFONLI ifs cal ArcsAtt Attached wavelength calibration Parameters to be specified Parameter Range Default P2PP Label SEQ SPECDITH TF F Spectral dithering Hidden parameters SEQ ARC TF T Night Arc SEQ FLATFIELD TF F Night Flat field DPR CATG CALIB CALIB Data product category DPR TECH IFU IFU Data product technique DPR TYPE WAVE LAMP WAVE LAMP Data product type 12 3 6 SINFONI_ifs_cal_LampFlatsAtt This template takes an internal lamp flat field with whatever setup was selected for the template executed immediately before All parameters are read from our local data base except for the spectral dithering flag There are two exposures taken 4 with spectral dither one with the halogen lamp on and the other with the lamp off We do not expect that internal flat fields will be needed at night time since the flexures are small even though not negligible SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 SINFONI_ifs_cal_LampFlatsAtt Attached lamp flat calibration Parameters to be specified
131. the first exposure The total integration time will be DIT NDIT Number of offset positions SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 70 SINFONL ifs obs AutoJitter IFS with jitter only no sky offsets Parameters to be specified Parameter Range Default P2PP Label DET DIT 0 3600 NODEFAULT Integration time DIT DET NDIT isf NODEFAULT umber of Integrations NDIT SEQ JITTER WIDTH 0 8 NODEFAULT Jitter box width SEQ NOFF 1 1000 NODEFAULT Number of offset positions SEQ SPECDITH TF F Spectral dithering INS OPTI1 NAME isf NODEFAULT SPAXEL size arcsec INS SETUP NAME isf NODEFAULT Instrument setup name Hidden parameters SEQ POISSON 1 100 10 SEQ RETURN TF T Return to Origin T F SEQ NEXPO 1 1000 1 Number of exposures per offset position INS MIRR1 NAME isf Ref SkySpider Position DPR CATG SCIENCE SCIENCE Data product category DPR TECH IFU IFU Data product technique DPR TYPE OBJECT OBJECT Data product type Figure 27 illustrates the execution sequence of the template for a relatively small if not far too small jitter box of about 2 5 arcseconds on the widest field of view of SINFONI SINFONI ifs obs AutoJitter Y E N bv d Position Angle 2 45 deg 7 Be 4 a l T e P 2 a 5 11 x Figure 27 An illustration of the offset sequence taken with the AutoJitter template 12 2 4 SINFONI ifs obs AutoJitterSpider Note that this template is not offered for the time be
132. tion policy on the Visitor Mode operations at the VLT are described at http www eso org sci observing phase2 VMGuidelines html and http www eso org sci facilities paranal sciops Visitors should be aware that per night about 30 minutes of their time may be taken within the framework of the SINFONI calibration plan 5 3 The influence of the Moon Moonlight does not noticeably increase the background in any of the SINFONI modes so there is no need to request dark or gray time for this reason However it is recommended not to observe targets closer than 30 to the Moon to avoid problems linked to the telescope guiding active optics system The effect is difficult to predict and to quantify as it depends on several parameters Just changing the guide star often solves the problem Visitors are encouraged to carefully check their target positions with respect to the Moon at the time of their scheduled observations Backup targets are recommended whenever possible and users are encouraged to contact ESO as early as possible in case of a severe conflict i e when the distance to the Moon is smaller than 30 To help determine the distance between targets and the Moon for given dates some useful tools are available at http www eso org sci observing tools ephemerides html However the Moon may affect the quality of the adaptive optics correction if the source used for wavefront sensing is fainter than R 15 mag In these cases re
133. tion In addition to the LGS a natural guiding star is therefore needed for the tip tilt control The LGS dichroic inserted in the optical path after the reflection on the IR dichroic transmits a narrow band centred on the LGS wavelength 589nm towards the CWFS and reflects the rest of the visible light towards the pointing sensor STRAP The differential focus between the LGS and an NGS can be written as d cosz D f H where z is the zenith angle 0 to 60 deg D the telescope diameter 8m f the beam f number f 17 1 and H the altitude of the sodium layer 80 to 100km The value of d varies between 100 and 250 mm It is compensated by inserting into the optical path a set of 4 folding mirrors mounted on a translation stage A second translation stage enables the length of this so called trombone to be adjusted to the current conditions In addition a compensating plate located in the trombone path corrects the astigmatism introduced by the transmission through the LGS dichroic Since the differential focus compensation occurs after the main optics relay the latter is not optimized for the LGS beam which suffers rather strong field aberrations The induced Strehl loss remains below 4 in K as long as the LGS is pointed within 5 arcsec of the LOS The STRAP unit is mounted on an XY table together with the STRAP lenses which pick up the guiding star in the 1 x2 FOV and images it on the STRAP head Figure 15 STRAP unit STRAP a
134. tions were good with 2 8ms coherence time and a guide star FWHM of 0 5 on the guide probe in the visible A DIT of 25s was used keeping the mean counts to 8000 ADUs for the central spaxel The time between DITs i e readout time was 20s The data was reduced using the SINFONI pipeline with the parameters chosen such that the individual data cubes were made from each exposure rather than all combined into one cube These are then spatially over sampled into 256 x 256 x 2218 pixel cubes from which we extracted 4 sub cubes outside the main telluric absorption bands at 2 03 2 04 jm 2 10 2 12 um 2 38 2 41 um and 2 10 2 42 um Afterwards 2 D gaussian PSFs were fitted to measure the PSF x and y positions as a function of time shown in Fig 3 This shows that the drift over 1 3 hours was 0 025 roughly the same order of magnitude as the precision for the flexure compensation Hereafter the results are reported for the first sub cube 2 03 2 04 um the findings with the other cubes SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 11 HIP69845 K 7 8 AParAngle 57 Median Peak PSF 1300 ADU 100 ADU Figure 4 Recovered images after injection of artificial secondary sources of different fluxes and distances The red circles indicate the expected positions of the artificial secondaries are similar Artificial secondaries were injected into the data which was then processed by filtering out the hot pixels and the
135. tten DM with cal unit t is always required to flatten the mirror to achieve a good image quality The shape of the deformable mirror will change critically with changing gravity vectors Only standard stars for which the shape of the PSF is irrelevant could be observed without flattening the DM Blind Offsets In case of blind offset acquisitions the coordinates and proper motions of the reference star must be entered into the Target section of the OB The offsets are defined from SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 65 the reference star to the target positive offsets for targets North East of the reference stars The relative offset between reference star and target should be accurately known to about a small fraction of the user selected field of view There is no interactive centering of the science target possible in blind offset mode 12 1 5 RRM acquisition templates The Rapid Response Mode RRM is being offered starting P78 both in no AO and NGS modes The RRM acquisition templates SINFONI isf acq noAOrrm and SINFONI isf acq NGSrrm are exactly identical to the SINFONI_isf_acq_noAO and SINFONI_isf_acq_NGS templates Only the name has been changed to display the rrm suffix Pupil tracking is currently not offered for this mode 12 2 Science Templates The four science observing templates provide various strategies for the nodding between object and sky positions and for the jitter
136. uisition NGSfast 2 SINFONI Acquisition LGS added to AO NGS acq time 9 SINFONI Centering of target AO and no AO 4 4 x DIT a NDIT SINFONI Instrument setup grating change 2 5 SINFONI Science exposure read out per DIT 0 07 SINFONI Detector setup overheads per DIT x NDIT 0 3 Note 1 for the Acquisition AO NGS or LGS modes the DIT and NDIT refer to the ones requested for the AO guide star NGS or TTS Note 2 The instrument set up is usually absorbed in the telescope preset Changing the plate scale within an OB is very fast 10s and will not be charged as overhead Changing grating within an OB is very slow 2 5 min on average The no AO acquisition takes 3 minutes mostly used to drive in the calibration fiber close the AO loop once in order to flatten the deformable mirror and drive out the fiber This way you obtain the optimal image quality at the telescope preset for your observations SINFONI User Manual Version 93 2 VLT MAN ESO 14700 3517 28 6 The SINFONI data reduction pipeline This section intends to provide a short overview of the frames required by the pipeline as well as a very brief overview of the data reduction steps For full description of the data reduction procedures please refer to the SINFONI Pipeline User Manual linked from http www eso org sci software pipelines sinfoni sinfo pipe recipes html and the SINFONI Data reduction cookbook http www eso org sci facilities paranal i

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