Proposals for IRAM Telescopes
Contents
1. Large Programmes category If time has already been given to a project but turned out to be insufficient explain the reasons e g indicate the amount of time lost due to bad weather or equipment failure if the fraction of time lost is close to 100 don t rewrite the proposal except for an introductory paragraph For continu ation of proposals having led to publications please give references to the latter EMIR Overview The spectral line receiver EMIR Eight MlIxer Receiver which was installed in spring 2009 is op erational without any major complications The re ceiver operates in the 3 2 1 3 and 0 9mm atmo spheric windows Fig in each of which it pro vides two orthogonal linear polarization channels EMIR offers very competitive noise temperatures a stable alignment between polarizations and bands and other practical advantages The four EMIR bands are designated as E090 E150 E230 and E330 according to their approx imate center frequencies in GHz Tab shows the main current characteristics of EMIR and in dicates the upgrades planned during the summer semester Three bands will then be equipped with two sideband 2SB mixers and only the E150 band has a single sideband SSB mixer The 2SB mixers offer 8 GHz of instantaneous bandwidth per band width and polarization whereas the SSB mixer has only 4 GHz per polarization After the upgrade the total EMIR bandwidth will increase from 64 to 104 GHz2. SPECTRAL spectral correlator unit tuning PLOT control of the plot parameters A typical session would be choice of receiver tuning line xyz 93 2 lsb 6500 choice of the correlator windows narrow Q3 Q3 correlator unit 1 on entry 1 15 spectral 1 20 600 narrow 1 correlator unit 2 on entry 1 spectral 2 20 735 narrow 1 correlator unit 3 on entry 1 spectral 4 320 300 narrow 1 correlator unit 4 on entry 2 spectral 4 320 666 narrow 2 The first step above choice of receiver tuning line xyz 93 2 lsb 6500 would produce a plot showing the full 3 6 GHz bandwidth delivered by the receivers that is acces sible to WideX in dual polarization Coordinates and Velocities The interferometer operates J2000 0 coordinate system Please do not forget to specify LSR velocities for the sources For pure continuum projects the spe cial velocity NULL no Doppler tracking can be used Any later request for a swap of targets has to be submitted for approval to the IRAM director and to be justified by new evidence or exceptional circumstances in the equatorial Sun Avoidance For safety reasons a sun avoidance limit is enforced at 35 degrees from the sun We are working to further reduce the sun avoidance limit for forthcom ing semesters Mosaics The PdBI has mosaicing capabilities but the point ing accuracy may be a limiting factor at the highest frequencies Please contact the
3. length 3 the MAMBO2 bolometer array with 117 pixels operating at 1 2mm Emphasis will be put on observations at the longer wavelengths Observations at wavelengths lt 1 3 mm will be scheduled toward the end of the semester in pools which allow to optimize the observations according to weather conditions The pool structure was successfully improved by including a new queue for projects requiring the best weather Projects in this new queue are observed when the column of preciptable water vapor drops below 2mm and when other practical conditions wind atmospheric stability are fulfilled We continue to call for Large Programmes using any of the three instruments Proposers are requested to use the time estima tors which are available online via the IRAM 30m webpage What is new Fourier Transform Spectrometers The im plementation and commissioning of the new Fast Fourier Transform Spectrometers FTS is proceed ing as planned Two blocks of FTS are available since 1 Dec 2010 each block covering a contiguous 4 GHz band The spectral resolution of these FTS is fixed to 195 kHz This new backend is available for regular observations with EMIR in all observing modes except for polarimetry Work is in progress 1 to increase the FTS band width up to 32 GHz at 195 kHz resolution and 2 to provide a higher spectral resolution of 50 kHz This change involves also a major upgrade of the IF sytem If installation an
4. and W Wild 1998 A amp A Suppl 133 271 Short guide to VESPA G Paubert IRAMES otherDocuments manuals vespa_ug ps First results from the IRAM 30m telescope im proved thermal control system J Pe alver A Greve and M Bremer 2002 IRAM Newsletter No 54 8 A Versatile IF Polarimeter at the IRAM 30m and A Sievers 1998 9 10 11 12 H Wiesemeyer S Navarro and M Torres in Polarimetry in Astronomy Ed Fineschi Proc of SPIE Vol 4843 272 283 2003 XPOL the correlation polarimeter at the IRAM 30m telescope Thum C Wiesemeyer Navarro S and Morris D PASP 120 777 2008 D Morris 13 H Paubert G These reports are available upon request see also previous Newsletters from Mrs C Berjaud IRAM Grenoble e mail berjaud iram fr Cal ibration related papers may also be found at TRAMES TRAMES mainWiki CalibrationPaper Clemens Thum amp Carsten Kramer News from the Plateau de Bure Interferometer Aluminum panels for antennas 1 and 6 Following the reflector upgrades of antennas 4 2008 and 2 2009 the remaining two antennas 1 and 6 were equipped with aluminum panels in the summer and fall of 2010 Work on antenna 1 was fin ished on June 28 and antenna 6 followed on October 17 The surfaces of both antennas were subsequently adjusted to accuracies of better than 50 wm rms in a series of holographic measurements and panel ad justments All
5. of which up to 32 GHz are available simulta neously Both polarizations of a given band will always be tuned to the same frequency as they share a single common local oscillator The tuning ranges of the 4 bands and the typical receiver noise temperatures are listed in Tab The image band rejection g as measured in the laboratory is always better than 10 db The observer at the telescope cannot however re measure anymore this sometimes critical quantity Below the lower frequency end of the tuning range v lt 83 GHz the behavior of g must be expected to be erratic and such observations are therefore discouraged EMIR provides a permanently available high sen sitivity E330 band opening this atmospheric win dow for regular use under very good weather condi tions The frequency range of this band see Tab currently limited at the upper end by LO power is planned to be extended up to 360 GHz Selection of EMIR bands Before reaching the Nasmyth mirrors the beams of the four EMIR bands pass through warm optics that contain switchable mirrors and dichroic elements for redirection of the beams towards calibration loads and for combining beams In its simplest mode the warm optics unit selects one single EMIR band for observation This mode avoids the use of the slightly Table 1 EMIR Frontend current status and planned IF band 25B dual sideband mixers SSB single side CALL FOR OBSERVING PROPOSALS ON THE 30M TE
6. IF band It would be natural to tune the receivers such that the selected sky frequency corresponds to the mid dle of the IF bandwidth i e 6 0 GHz However this corresponds to the limit between Q2 and Q3 If your project depends on the narrow band correlator it is therefore highly recommended to center a line at the center of a quarter see Section ASTRO below In all bands the receivers offer best performance in terms of receiver noise and sideband rejection in Q3 i e the line should usually be centered at an IF 1 frequency of 6500 MHz Spectral units of the narrow band correlator The narrow band correlator has 8 independent units which can be placed anywhere in the 100 1100 MHz band 1GHz bandwidth 7 different modes of configuration are available characterized in the following by couples of total bandwidth number of channels In the 3 DSB modes 320MHz 128 160MHz 256 80MHz 512 see Table the two cen tral channels may be perturbed by the Gibbs phe nomenon if the observed source has a strong contin uum When using these modes it is recommended to avoid centering the most important part of the lines in the middle of the band of the correlator unit In the remaining SSB modes 160MHz 128 80MHz 256 40MHz 512 20MHz 512 the two cen tral channels are not affected by the Gibbs phe nomenon and therefore these modes may be prefer able for some spectroscopic studies Coordinates and Velocities Spacing Channe
7. added in the figure caption The referees may then consult the electronic version of proposal Soon after the deadline the IRAM Scientific Sec retariat sends an acknowledgement of receipt to the Principal Investigator of each proposal correctly re ceived together with the proposal registration num ber Note that the web facility allows cancellation and modification of proposals before the deadline The facility also allows to view the proposal in its fi nal form as it appears after re compilation at IRAM We urge proposers to make use of this feature as we always receive a number of corrupted proposals figures missing blank pages etc Valid proposals contain the official cover page one or more pages of technical information up to two pages of text describing the scientific aims and up to two pages of figures tables and references Nor mal proposals should not exceed 6 pages except for additional technical pages Longer proposals will be cut We continue to call for Large Observing Pro grammes see P Cox at the end of this Call for Pro posals The Large Programmes may have up to 4 pages for the scientific justification plus cover page the technical pages and 2 pages for supporting ma terial The current versions of the proposal templates for the 30m telescope prop 30m tex and for the inter ferometer prop pdb tex must be used together with the current ATEX style file proposal sty All three files may be downloaded
8. and to schedule the 5D configuration between June and October We strongly encourage observers to submit pro posals that can be executed during summer operat ing conditions To keep the procedure as simple as possible we ask to focus on o observations requesting the use of the 2mm and 3mm receivers o circumpolar sources or sources transiting at night between June and September o observations that qualify for the 5D 6D and 6C configurations Proposal category Proposals should be submitted for one or more of the seven categories 3MM Proposals that ask for 3mm data 2MM Proposals that ask for 2mm data 3mm re ceivers can be used for pointing and calibration purposes but cannot provide any imaging 1 3MM Proposals that ask for 1 3mm data 3mm receivers can be used for pointing and calibra tion purposes but cannot provide any imag ing During the summer semester proposals requesting the extended tuning range 256 267 GHz will be carried out on a best effort basis only 0 8MM If your proposal requests observations us ing the new band 4 277 to 371 GHz receivers please check this bullet Please note that the observations can only be carried out at the end of the summer semester on a best effort basis TIME FILLER Proposals that have to be considered as background projects to fill in periods where the atmospheric conditions do not allow map ping to fill in gaps in the scheduling or even to
9. can be observed but with the two polarizations avail able Each polarization delivers a 3 6GHz band width from IF 4 2 to 7 8GHz The two 3 6 GHz bandwidths coincide in the sky frequency scale The wide band correlator WideX gives access to the two 3 6GHz wide IF bands simultane ously WideX provides a fixed spectral resolution of 1 95 MHz over the full bandwidth and is available in parallel to the narrow band correlator 14 CALL FOR OBSERVING PROPOSALS ON THE PLATEAU DE BURE INTERFEROMETER Band 1 RF range GHz 80 116 Trec K LSB 40 55 Trec K USB 40 55 Gim dB 10 RF LSB GHz 80 104 RF USB GHz 104 116 Band 2 Band 3 Band 4 129 174 201 267 277 371 30 50 40 60 40 70 40 80 50 70 40 70 12 10 12 8 20 129 165 201 264 277 359 164 174 264 267 289 371 center of the 4 2 7 8 GHz IF band IF processor and narrow band correlator The narrow band correlator accepts as input two signals of 1 GHz bandwidth that must be selected within the 3 6 GHz delivered by the receiver In practice the IF processor splits the two input 4 2 7 8GHz bands in four 1GHz wide quarters la beled Q1 Q4 Two of these quarters must be se lected as narrow band correlator inputs The system allows the following choices first correlator entry can only be Q1 HOR or Q2 HOR or Q3 VER or Q4 VER second correlator entry can only be Q1 VER or Q2 VER or Q3 HOR or Q4 HOR where HOR and VER refer to the two polariz
10. encountered in the course of the observa tions and if needed adjust the program scheduling The proprietary period ends 18 months after the end of the last scheduling semester in which the Large Program was observed The raw data and processed data then enter the public domain An extension of this proprietary period may be granted in exceptional cases only A corresponding request will have to be submitted to the IRAM director Because of the scope of the Large Programs and the need to explain the organization of the project Large Program proposals will have a maximum length of 4 pages not including figures tables or references instead of the 2 pages for normal proposals Large observing program proposals should be submitted using the standard proposal templates just check the Large Program bullet on the cover page The following sections should be included i Scientific Rationale ii Immediate Objective iii Feasibility and Technical Justification and iv Organizational Issues For the Plateau de Bure interferometer the latter section must include a consideration of sun avoidance constraints and configuration scheduling The scientific evaluation of the Large Program proposals will be done by the Program Committee at large all 12 members except if there is a direct implication of one of the members in the proposal External reviewers will be asked to evaluate Large Programs if needed In addition to the scientific evaluation th
11. from http www iram fr GENERAL submission proposal html Do not change the font type or size and do not ma nipulate the style file In case of problems contact the IRAM secretary e mail berjaud iram fr Please also indicate on the proposal cover page whether your proposal is or is not a resubmission of a previously rejected proposal or a continuation of a previously accepted interferometer or 30m pro posal We request that the proposers describe very briefly in the introductory paragraph automatically generated header Proposal history why the pro posal is being resubmitted e g improved scientific justification or is proposed to be continued e g last observations suffered from bad weather Short spacing observations on the 30m tele scope should directly be requested on the interfer ometer proposal form A separate proposal for the 30m telescope is not required The interferometer proposal form contains a bullet labelled 30M short spacings which should then be checked The user will be prompted to fill in an additional paragraph in which the scientific need for the short spacings should be described It is essential to give here all ob servational details including size of map sampling density and rms noise spectral resolution receiver configuration and time requested A mailing list has been set up for astronomers in terested in being notified about the availability of a new Call for Proposals A
12. observing run If your observations with the 30m telescope result in a publication please acknowledge this in a footnote Based on observations with the IRAM 30 m telescope IRAM is supported by CNRS INSU France the MPG Germany and the IGN Spain A copy of the publication should be sent to M Bremer bremer iram fr References 1 Astigmatism in reflector antennas measure ment and correction A Greve B Lefloch D Morris H Hein S Navarro 1994 IEEE Trans Ant Propag AP 42 1345 2 Frequency switching at the 30m telescope C Thum A Sievers S Navarro W Brunswig J Pe alver 1995 IRAM Tech Report 228 95 available at the spanish web site REFERENCES 3 Cookbook formulae for estimating observing times at the 30m telescope M Gu lin C Kramer and W Wild The 30m Manual A Handbook for the 30m Telescope version 2 W Wild 1995 IRAM Tech Report 377 95 also available from the 30m_ web site 5 GILDAS web page at http www iram fr IRAMFR GILDAS 6 Line Calibrators at A 1 3 2 and 3mm R Mauersberger M Gu lin J Mart n Pintado C Thum J Cernicharo H Hein and S Navarro 1989 A amp A Suppl 79 217 The Pointing of the IRAM 30m Telescope A Greve J F Panis and C Thum 1996 A amp A Suppl 115 379 The gain elevation correction of the IRAM 30m Telescope A Greve R Neri A amp A Suppl 132 413 The beam pattern of the IRAM 30m Telescope A Greve C Kramer
13. page Very demanding proposals e g observa tions using E330 above 300 GHz or some very deep and or high frequency continuum observations may need pwv values lt 2mm These observations will be scheduled in a pool Frequency switching Frequency switching is available for both HERA po larizations as well as for EMIR This observing mode is interesting for observations of narrow lines where flat baselines are not essential although the spectral baselines with HERA are among the best known in frequency switching Certain limitations exist with respect to maximum frequency throw lt 45 km s backends phase times etc for a detailed report see B This report also explains how to identify mesospheric lines which may easily be confused in some cases with genuine astronomical lines from cold clouds Organizational aspects Pooled observing As in previous semesters we plan to pool the ac cepted high frequency A lt 1 3mm proposals This includes bolometer HERA and those EMIR pro posals which principally request the E 230 and E 330 bands These high frequency proposals will be com bined with less weather dependent proposals at lower frequencies in several pool sessions Proposals with particularly strong demands on weather qual ity e g heterodyne observations at v gt 300 GHz very deep bolometer maps will be included in these pools where they get precedence as soon as the pre cipitable water vapor column pwv falls
14. to this mailing list is on the IRAM web page The list presently includes all principal investigators of proposals for IRAM telescopes during the last 2 years Please ver ify that your email address in this list is correct J M Winters amp C Thum 2 CALL FOR OBSERVING PROPOSALS ON THE 30M TELESCOPE Travel funds for European astronomers Observations using IRAM telescopes continue to be supported by RadioNet under the European Frame work Programme 7 A budget somewhat reduced compared to the 2004 2008 period is available for travel by European astronomers through the Trans National Access TNA Programme As before travel may be supported to the 30m telescope for observation contact C Thum and to Grenoble for reduction of interferome ter data contact R Neri Detailed information about the eligibility policies and travel claims can be found on the at http www radionet eu org The Principal In vestigators of IRAM proposals eligible for TNA funding will be informed individually R Neri amp C Thum Call for Observing Proposals on the 30m Telescope Summary Proposals for three types of receivers will be consid ered for the coming summer semester 1 June 30 Nov 2011 1 the heterodyne receiver EMIR consisting of dual polarization mixers operating in the four bands at 3 2 1 3 and 0 9mm wavelengths 2 the 9 pixel dual polarization heterodyne re ceiver array HERA operating at 1 3mm wave
15. 1 3mm Use 45 Jy K at 0 8mm Tyys is the system temperature Tsys 100K below 110GHz 180K at 115GHz 180K at 150 GHz and 250K at 230GHz for sources at 6 gt 20 and for typical summer conditions Use Tsys 500 K at 350 GHz is an efficiency factor due to atmospheric phase noise and instrumental phase jitter 0 9 at 3mm 0 8 at 2mm and 0 6 at 1 3mm in typical summer conditions Use 7 0 50 at 0 8mm N is the number of antennas 5 and Ne is the number of configurations 1 for D 2 for CD 1 for C Ton is the on source integration time per con figuration in seconds 2 to 8 hours depending on source declination Because of various cali bration observations the total observing time is typically 1 6 Ton B is the spectral bandwidth in Hz up to 2 GHz for continuum 40kHz to 2 5 MHz for spectral line according to the spectral setup of the nar row band correlator and from 2 MHz for line projects up to 3 6 GHz for continuum projects using WideX Npo is the number of polarizations 1 for sin gle polarization and 2 for dual polarization see section Correlator for details Investigators have to specify in the technical justification and on the Technical Sheet the 1 sigma noise level which is necessary to achieve each individual goal of a proposal and particularly for projects aiming at deep integrations Correlator IF processor and WideX At any given time only one frequency band
16. IRAM Plateau de Bure Interferometer includes documents of general inter est to potential users and more specialized docu ments intended for observers on the site IRAM on duty astronomers operators or observers with non standard programs All documents can be retrieved on the Internet at TRAMFR PDB docu html Note however that not all the documentation on the web has already been updated with respect to the current receivers All information presently available on the current receiver system is given in this call for proposals in the Introduction to the IRAM Plateau de Bure Interferometer at and in the Calibration CookBook available at IRAMFR GILDAS doc html1 pdbi cookbook html Publication Publications resulting from Plateau de Bure inter ferometer observations should acknowledge this in a footnote Based on observations carried out with the IRAM Plateau de Bure Interferometer IRAM is supported by INSU CNRS France MPG Ger many and IGN Spain Please send a copy of the paper to Michael Bremer bremer iram fr Finally we would like to stress again the impor tance of the quality of the observing proposal The IRAM interferometer is a powerful but complex instrument and proposal preparation requires special care Information is available ia ihis altandat The IRAM staff can help in case of doubts if contacted well before the deadline Note that the proposal should not only justify the scien tific int
17. LESCOPE upgrades Sky frequencies Fsky refer to the center of the band mixers H V horizontal and vertical polarizations Ts is the SSB receiver temperature in single band observations left For dual band observations Tap includes a 15 K noise contribution from the dichroics right mixer type EMIR F ky band GHz E090 83 117 28B E150 129 174 SSB E230 200 267 SSB 2SB E330 260 350 2SB polari zation G bandwidth Typ Gim K dB combinations Tab Hz E0 2 E1 3 E0 1 K i IRAM 30m for 1mm and 4mm pwv ATM Vers Jan07 Dn i i i l i i L rR a aa 1 a A M gt 0 8 h mn J MAN E z M Vy Ez N d heb MS 7 E 0 6 H 4 om Wy IIE E iii co a 0 4 L 4 E oo Spi S NT cs La TW L VWI J 0 2 1 4 Ji i i 4 e EO Bl E2 ES 0 Uf A NY 100 200 300 Frequency GHz Figure 1 Atmospheric transmission at the 30m site between 60 and 400 GHz for 1 and 4mm of precipitable water vapor derived from the ATM model The EMIR bands are indicated and the frequencies of a few important molecular transitions are marked lossy dichroic elements and therefore offers the best receiver noise temperatures The warm optics includes dichroic mirrors which combine the beams o
18. Proposals for IRAM Telescopes The deadline for submission of observing proposals on IRAM telescopes both the interferometer and the 30m is 17 March 2011 17 00 CET UT 1 hour The scheduling period extends from 1 June 30 Nov 2011 Proposals should be submitted through our web based submission facility Instructions can be found on our web page at URL http www iram fr GENERAL submission submission html Detailed information on time estimates special ob serving modes technical information and references for both the IRAM interferometer and the IRAM 30m telescope can be found http www iram institute org and then following the links under Proposals The submission facility will be opened about three weeks before the proposal deadline Proposal form pages and the 30m time estimator are available now Please avoid last minute submissions when the network could be congested As an insurance against network congestion or failure we still accept in well justified cases proposals submitted by fax to number 33 476 42 54 69 or by ordinary mail addressed to IRAM Scientific Secretariat 300 rue de la piscine F 38406 St Martin d Heres France Proposals sent by e mail are not accepted Color plots will be printed copied in grey scale Proposals are evaluated on the basis of the paper copy If color is considered essential for the understanding of a specific figure a respective remark should be
19. Science Operations Group sog iram fr in case of doubts Local Contact A local contact will be assigned to every A or B rated proposal which does not involve an in house collaborator He she will assist you in the prepara tion of the observing procedures and provide help to reduce the data 16 CALL FOR OBSERVING PROPOSALS ON THE PLATEAU DE BURE INTERFEROMETER Assistance write to sog iram fr is also provided before a deadline to help newcomers in the prepa ration of a proposal Depending upon the program complexity IRAM may require an in house collabo rator instead of the normal local contact Data reduction Proposers should be aware of constraints for data reduction o We recommend that proposers reduce their data in Grenoble For the time being remote data reduction can only be offered in excep tional cases and with some restrictions enforced on the VISITOR accounts Please contact your local contact if you re interested in this possi bility o We keep the data reduction schedule very flexi ble but wish to avoid the presence of more than 2 groups at the same time in Grenoble Data reduction will be carried out on dedicated com puters at IRAM Please contact us in advance o In certain cases proposers may have a look at the uv tables as the observations progress If necessary and upon request more informa tion can be provided Please contact your lo cal contact or PdBI s Science Operations Group sog ira
20. anged in the form of a center filled square and are separated by 6 CALL FOR OBSERVING PROPOSALS ON THE 30M TELESCOPE 24 Each beam is split into two linear polarizations which couple to separate SIS mixers The 18 mixers feed 18 independent IF chains Each set of 9 mix ers is pumped by a separate local oscillator system The same positions can thus be observed simultane ously at any two frequencies inside the HERA tun ing range 210 276 GHz for the first polarization and 210 242 for the second polarization A derotator optical assembly can be set to keep the 9 pixel pattern stationary in the equatorial or horizontal coordinates Receiver characteristics are listed on the Recent observations have shown that the noise temperature of the pixels of the second polarization array may vary across the 1 GHz IF band The high est noise occurs towards the band edges which are unfortunately picked up when HERA is connected with VESPA whose narrow observing band is lo cated close to the lower edge of the 1 GHz band Therefore while not as important for wide band ob servations with centered IF band the system noise in narrow mode is higher factor 1 5 2 as com pared to the first polarization array We do not rec ommend to use the second polarization for frequen cies gt 241 GHz HERA can be connected to three sets of backends gt VESPA with the following combinations of nominal resolution kHz and maximum band width MH
21. aragraph Such propos als will however be particularly scrutinized On the other extreme if only strong sources are observed and moderate weather conditions are sufficient the proposal may be used as a backup in the observing 3 see also the Technical report by D Teyssier and A Siev ers on a special fast mapping mode IRAM Newsletter No 41 p 12 Aug 1999 pool The proposal should point out this circum stance as it affects positively the chance that the proposal is accepted and observed Questions concerning the MAMBO pool organiza tion can be directed to the scheduler thum iram fr or to the MAMBO pool coordinator Guillermo Quintana Lacaci quintana iram es The Telescope This section gives all the technical details of obser vations with the 30m telescope that the typical user will have to know A concise summary of telescope characteristics is published on the IRAM web pages Pointing and Focusing With the systematic use of inclinometers the tele scope pointing became much more stable Pointing sessions are now scheduled at larger intervals The fitted pointing parameters typically yield an abso lute rms pointing accuracy of better than 3 7 However larger deviations can occur around sun set or sunrise in which case we recommend more frequent pointings every 1 or 2 hours depending on the beam size The eight individual receivers of EMIR are very well aligned with each other Offsets between polarizat
22. ation If you are in terested in this mode of observing specify it as a special requirement in the proposal form IRAM will then decide which proposals can actually be ac cepted for this mode 10 Remote observing This observing mode where the remote observer actually controls the telescope very much like on Pico Veleta is available from the IRAM offices in Granada and Grenoble and from the MPIfR Bonn and from OAN in Madrid If you are planning to use remote observing please contact the Astronomer on Duty for Granada Clemens Thum for Greno ble J Alcolea for Madrid or Dirk Muders for Bonn well in advance of your observing run As a safeguard please email observing instructions and macros to the AoD and or operator In special cases experienced observers may con duct remote observations from individual com puters at their home institutes Such observa tions need agreement by the station manager kramer iram es who must be contacted at least two weeks in advance Reminders For any questions regarding the telescope and the control programs we recommend to con sult the summary of telescope parameters and the NCS web pages The applied calibration procedure is explained in depth in a special report entitled The astronomer on duty schedule is available at http www iram es IRAMES mainWiki Astro nomerOnDutySchedule The AoD may be contacted for any special questions concerning the preparation of an
23. ations Quarter Q1 Q2 Q3 Q4 IF1 GHz 4 2 5 2 5 6 6 7 6 8 7 8 input 1 HOR HOR VER VER input 2 VER VER HOR HOR Note that the combination VER VER is not al lowed How to observe two polarizations To observe si multaneously two polarizations at the same sky fre quency one must select the same quarter Q1 or Q2 or Q3 or Q4 for the two narrow band correlator en tries This will necessarily result in each entry seeing a different polarization The system thus give access to 1GHz x 2 polarizations How to use the full 2GHz bandwidth If two dif ferent quarters are selected any combination except VER VER is possible a bandwidth of 2 GHz can be analyzed by the narrow band correlator Only one polarization per quarter is available in that case this may or may not be the same polarization for the two chunks of 1 GHz Is there any overlap between the four quarters In fact the four available quarters are 1 GHz wide each but with a small overlap between some of them Q1 is 4 2 to 5 2 GHz Q2 is 5 to 6 GHz Q3 is 6 to 7 GHz and Q4 is 6 8 to 7 8 GHz This results from the com bination of filters and LOs used in the IF processor Is the 2GHz bandwidth necessarily continuous No any combination except VER VER of two quarters can be selected Adjacent quarters will re sult in a quasi continuous 1 8 2GHz band Non adjacent quarters will result in two independent 1 GHz bands Where is the selected sky frequency in the
24. below 2mm and other conditions are fullfilled A correct specifi cation of the pwv on the technical summary page is therefore very important The proposals participating in the pools will be observed by the PIs and Co PIs of partici pating projects and IRAM staff The pool obser vations will be organized by the pool coordina tors Guillermo Quintana Lacaci MAMBO2 1 and Manuel Gonzalez HERA The participating pro posals are grouped according to their demand on weather quality and they get observed following the priorities assigned by the program committee The organization of the observing pools are described on Bolometer and heterodyne proposals which are particularly weather tolerant qualify as backup for the pools Participation in the pools is voluntary and the respective box on the proposal form should be checked Questions concerning the pool organization can be directed to the scheduler thum iram fr or the Pool Coordinators Guillermo Quintana Lacaci quintanaQ iram es and Manuel Gonzalez gonzalez iram es Service observing To facilitate the execution of short lt 8 h pro grammes we propose service observing for some easy to observe programmes with only one set of tun ings Observations are made by the local staff using precisely laid out instructions by the principal in vestigator For this type of observation we request an acknowledgement of the IRAM staff member s help in the forthcoming public
25. configuration and we moved to a compact D like configuration on December 18 for the commission ing of band 4 Science verification observations in band 4 could be done at the beginning of the year and we moved the array to the B configuration on January 5 in order to prepare for the long haul to 11 the A configuration Because of large amounts of snow on the tracks and of adverse weather condi tions around mid of January the move to this most extended configuration had to be delayed until Jan uary 18 The array was kept in the A configuration until mid February and moved back into the second most extended configuration B on February 10 We currently anticipate to go to the C configuration by beginning of March The switch to the most compact D configuration is not foreseen before April Global VLBI observations which include the array in the 3mm phased array mode are scheduled from May 5 to 10 2011 According to these plans it will not be possible to complete projects requesting deep in tegrations using the compact configurations before the end of the semester As far as A rated projects are concerned we hope to bring most of these to completion before the end of the current winter semester B rated projects are likely to be observed only if they fall in a favorable LST range We remind users of the Plateau de Bure interferometer that B rated proposals which are not started before the end of the winter semester have to be resubmi
26. d commissioning work out as planned we expect that the expanded FTS fea tures become available during the summer semester A more detailed description of the 32GHz FTS sys tem is given in the IRAM Newsletter of spring 2011 EMIR upgrade The large bandwidth of EMIR will be increased further during the semester The mixers used for the 230 and 330 GHz bands will be replaced by dual sideband 2SB mixers of the de sign already installed for the E090 band The E 230 and E330 bands will then also have 32 GHz band width each 2 sidebands x 2 polarizations x 8 GHz of instantaneous bandwidth New continuum backends We are installing new broadband continuum backends which fully cover the bandwidth provided by EMIR The cur rent continuum detectors have a bandwidth of only 1 GHz As none of the above three upgrades have yet been commissioned on the telescope we ask the proposers to base their estimates on the current available sys tem Use of the upgraded system will be on a shared risk basis Further information about the upgrades will be provided in due time to the community Ob servers should make it clear in their proposals if the expanded features are essential in reaching their goals The complete text of the Call for Proposals can be retrieved as a pdf file from the IRAM web sitelat http www iram fr GENERAL calls si1 s11 pdf EMIR Non trivial changes with respect to the previous Call for Proposals are marked in r
27. ds E090 and E230 Po larimetry using the bands E150 and E330 has to wait for additional hardware and commission ing Astronomers interested in using XPOL are in vited to check with Helmut Wiesemeyer or Clemens Thum Observing time estimates This matter needs special attention as a serious time underestimate may be considered as a sure sign of sloppy proposal preparation We strongly recom mend to use the current time estimator on line at the Granada web site which handles EMIR HERA and MAMBO2 If very special observing modes are proposed which are not covered by the Time Estimator pro posers must give sufficient technical details so that their time estimate can be reproduced In particular the proposal must give values for Tgys the spectral resolution the expected antenna temperature of the signal the signal noise ratio which is aimed for all overheads and dead times and the resulting observ ing time Proposers should base their time request on nor mal summer conditions corresponding to 7mm of precipitable water vapor pwv Conditions during afternoons can be degraded due to anomalous re fraction The observing efficiency is then reduced and the flux temperature calibration is more uncer tain than the typical 10 percent possibly slightly more for bolometer observations Proposers requesting observations which need pwv values lower than 7mm should enter the max imum acceptable pwv value on the Technical sum mary
28. ed C Thum amp C Kramer Applications The official proposal cover page and the second page for the Technical Summary should be filled in with great care All information on these pages is trans ferred to the IRAM proposal database Attention should be given to Scheduling constraints where the proposer can enter dates where he she is not avail able for observing Proposers requesting observa tions which need atmospheric opacities better than typical for the semester corresponding to 7mm pwv in summer and 4mm in winter should give the max imum acceptable value of precipitable water vapor in the corresponding table of the Technical Summary In order to avoid duplication of observations and to protect already accepted proposals we keep a computerized list of targets We ask you to fill in carefully the source list in equatorial J2000 coordi nates This list must contain all the sources and only those sources for which you request observ ing time Your list must adhere to the format indi cated on the proposal form sexagesimal notation If your source list is longer than 15 sources that fit onto the cover page please use the 4TfXmacro extendedsourcelist A scientific project should not be artificially cut into several small projects but should rather be sub mitted as one bigger project even if this means 100 150 hours of observing time Note that large programs of particular scientific importance can be submitted in the
29. ed observations between differ ent RF bands e g band 1 and band 3 are possible in well justified cases they are however not very efficient Please contact the Interferometer Science Operations Group sog iram fr to discuss the fea sibility in case you are interested to use this mode The mixers for bands 1 2 and 3 are single sideband backshort tuned they will usually be tuned LSB except for the upper part of the fre quency range in all three bands where the mixers will be tuned USB The band 4 mixers are 2SB re ceivers operated in SSB mode They can be tuned LSB or USB throughout most of the accessible fre quency range The typical image rejection is 10dB 20 dB for band 4 Each IF channel is 3 6 GHz wide 4 2 7 8 GHz The wide band correlator WideX is able to pro cess both 3 6GHz wide IFs simultaneously with a fixed resolution of about 2MHz The narrow band correlator can process the two 3 6GHz wide IF channels one per polarization only partially A dedicated IF processor converts selected 1 GHz wide slices of the 4 2 7 8 GHz first IFs down to 0 1 1 1GHz the input range of the narrow band cor relator Further details are given in the section de scribing the correlator setup and the IF processor Signal to Noise The rms noise can be computed from Taye 1 g ie i f n Na Na 1 N TonB Npol where 13 Jpx is the conversion factor from Kelvin to Jan sky 22 Jy K at 3mm 29 Jy K at 2mm and 35 Jy K at
30. ere will be an assessment of the technical feasibility by IRAM staff Note that a Large Program will either be accepted in its entirety or rejected there will be no B rating backup status nor a partial acceptance rejection of the proposal For the summer semester 2011 the call for Large Programs will be open for the 30m telescope and the Plateau de Bure interferometer For the 30m telescope Large Programs may consider using HERA and MAMBO as well as EMIR Due to high pressure of Large Programs requesting the 1mm band at the Plateau de Bure interferometer it should be noted that new Large Programs requesting 1 mm observations as part of their project will likely not be scheduled this summer Pierre Cox
31. erest but also the need for the Plateau de Bure Interferometer Jan Martin WINTERS Publication 17 Large observing programs IRAM offers the possibility to apply for observing time in the framework of a Large Program for the 30 meter telescope and the Plateau de Bure interferometer A Large Program should require a minimum of 100 hours of observing time spread over a maximum of two years i e 4 contiguous semesters IRAM will accept a limited number of Large Programs to be carried out per semester and instrument 30 meter and Plateau de Bure interferometer allocating a maximum of 30 of observing time to such projects The Large Program should address strategic scientific issues leading to a breakthrough in the field Large Programs should be coherent science projects not reproducible by a combination of smaller normal pro posals The Large Program proposals should contain a solid management plan ensuring an efficient turnover including data reduction analysis and organization of the efforts Because of the large investment in observing time but also of the inherent support from IRAM it is advised that Large Programs involve one or more IRAM internal collaborators During the execution period of the Large Programs ideally before mid term the team leading the Large Program should report to IRAM about the preliminary results and possible technical difficulties so that IRAM could assess the progress made assist with any problems
32. ers for polarimetry The many VESPA configura tions and user modes are summarized in a and in a but are best visualised on a demonstration pro gram which can be downloaded from our web page at http www iram fr IRAMFR PV veleta htm Connected to a set of 4 IF schannels of EMIR VESPA typically provides up to 12000 spectral channels on average 3000 per receiver Up to 18000 channels are possible in special configura tions Nominal spectral resolutions range from 3 3 kHz to 1 25 MHz Nominal bandwidths are in the range 10 512 MHz VESPA basebands can be offset from band center up to 250 MHz outer edges of the baseband When VESPA is connected to HERA up to 18 000 spectral channels can be used with the following typical combinations of nominal resolution kHz and maximum bandwidth MHz 20 40 40 80 80 160 320 320 1250 640 The 4 MHz filterbank consists of nine units Each unit has 256 channels spacing of 4 MHz spec tral resolution at 3 dB is 6 2 MHz and thus covers a total bandwidth of 1 GHz The 9 units are designed for connection to HERA but a subset of 4 units can also be connected to EMIR The wideband autocorrelator WILMA con sists of 18 units They can be connected to the 18 detectors of HERA or to EMIR Each unit provides 512 spectral channels spaced out by 2 MHz and thus covering a total band width of 1 GHz Each band is sliced into two 500 MHz subbands which are digitized with 2 bit 1 GHz samplers An info
33. ez iram fr the HERA pool coordinator may also be contacted Accepted HERA proposals will be pooled to gether in order to make more efficient use of stable 1 3mm observing conditions Questions concerning the HERA pool organization can be directed to the scheduler or the HERA pool coordinator MPIfR Bolometer array The bolometer array MAMBO 2 117 pixels is provided by the Max Planck Institut f r Radioas tronomie It consists of concentric hexagonal rings of horns centered on the central horn Spacing be tween horns is 20 Each pixel has a HPBW of n The effective sensitivity of MAMBO 2 for onoff observations is 40 mJys and 45 mJy s3 for mapping The rms in mJy of a MAMBO 2 map is typically rms 0 4f V VUscan As where Uscan in arcsec sec is the velocity in the scanning direction and As in arcsec is the step size in the orthogonal direction The factor f is 1 2 for sources of size lt 30 gt 60 It is assumed that the map is made large enough that all beams cover the source The sensitivities apply to bolo metric conditions stable atmosphere 7 250GHz 0 3 elevation 45 deg and application of skynoise filtering algorithms In cases where skynoise filter ing algorithms are not or not fully effective e g ex tended source structure atmosphere not sufficiently stable the effective sensitivity is typically about a factor of 2 worse The principal investigators of ac cepted proposals w
34. f two receivers in such a way that they look at the same position on the sky and have the same focus values within 0 3mm The fol lowing band combinations are possible E090 and E150 E090 and E 230 or E 150 and E330 Tab D The combination of bands is not polarization selec tive i e the combined beams will stay dual polar ization The loss of these dichroics which is small over most of the accessible frequency range in creases however the receiver temperatures by 10 15 K In a few particularly disadvantageous frequency combinations the increase of receiver noise may be substantially higher see the EMIR web site The observer is therefore advised to carefully eval uate whether an observation involving two different bands is more efficiently made in parallel or in series Connection to backends The remarkable bandwidth of EMIR of currently 64 GHz and soon 104 GHz faces two limitations of the existing 30m hardware 1 the four IF cables can transport only 4 GHz each the 4 x 4 GHz bot tleneck and 2 only at low spectral resolution are there enough backends to cover the 16 GHz which pass through the bottleneck These two limitations may soon be relaxed or overcome after the installation of a new IF trans port system and the expanded FTS backend In the HERA following we describe however only the current sit uation A IF switch box in the receiver cabin allows to select 4 EMIR channels of 4 GHz bandwidth each f
35. fill in periods when only a subset of the stan dard 5 antenna configurations will be available CALL FOR OBSERVING PROPOSALS ON THE PLATEAU DE BURE INTERFEROMETER These proposals will be carried out on a best effort basis only SPECIAL Exploratory proposals whose scientific in terest justifies the attempt to use the PdB array beyond its guaranteed capabilities This cat egory includes for example non standard fre quencies for which the tuning cannot be guar anteed non standard configurations and more generally all non standard observations These proposals will be carried out on a best effort basis only LARGE PROGRAM This category is offered on both IRAM instruments since the winter 2008 2009 observing period See Section Large Observing Programs for a detailed explanation The proposal category will have to be specified on the proposal cover sheet and should be carefully con sidered by proposers Configurations Configurations planned for the summer period are W08 E03 N07 N11 W05 W08 E03 N07 N11 N02 W05 W12 E10 N17 N11 E04 W09 Part of the projects will be scheduled at the end of the summer period when the six element array is ex pected to be back to operation Projects that should be observed with a subset of the five element array will be adjusted in uv coverage and observing time The following configuration sets are available o D is best suited for deep integration and coarse mapping exper
36. ill be requested to specify in the pool database which minimum atmospheric condi tions their observations need The bolometer arrays are mostly used in two ba sic observing modes ON OFF and mapping Pre vious experience with MAMBO 2 shows that the ON OFF reaches typically an rms noise of 2 3 mJy in 10 min of total observing time about 200 sec of ON source or about 400 sec on sky integra tion time under stable conditions Up to 30 percent lower noise may be obtained in perfect weather In this observing mode the noise integrates down with time t as vt to rms noise levels below 0 4 mJy The Telescope In the mapping mode the telescope is scanning in the direction of the wobbler throw default az imuth in such a way that all pixels see the source once A typical single mart with MAMBO 2 cov ering a fully and homogeneously sampled area of 150 x 150 scanning speed 5 per sec raster step 8 reaches an rms of 2 8 mJy beam in 1 9 hours if skynoise filtering is effective Much more time is needed see Time Estimator if sky noise filtering cannot be used The area actually scanned in this typical map must be much larger namely 8 0 6 5 if the EHK algorithm is used to restore properly ex tended emission This is because the wobbler throw the array size 4 the source extent and some margin for baseline determination must be added Shorter scans may lead to problems in restoring ex tended structure Mosaici
37. iments resolution 5 at 100 GHz This configuration provides both the highest sensitivity and the lowest atmospheric phase noise o CD i e the combination of C and D configura tion is well adapted for low angular resolution studies 3 5 at 100 GHz 1 5 at 230 GHz o Cis appropriate for mapping snapshot and size measurements and for detection experiments at low declination It provides a spatial resolution of 2 8 at 100 GHz Finally enter ANY in the proposal form if your project doesn t need any particular configuration Please consult the documentation An Introduction to the IRAM interferomete for further details Correlator Receivers All antennas are equipped with dual polarization re ceivers for the 3mm 2mm 1 3 mm and 0 8mm at mospheric windows The frequency range is 80 GHz to 116 GHz for the 3mm band 129 GHz to 174 GHz for the 2mm band 201 to 267 GHz for the 1 3mm band and 277 to 371 GHz for the 0 8mm band Each band of the receivers is dual polarization with the two RF channels one per polarization of one band observing at the same frequency The four different bands are not co aligned in the focal plane and therefore on the sky Due to the pointing off sets between the different frequency bands only one band can be observed at any time One of the three other bands is in stand by mode power on and lo cal oscillator phase locked and is available e g for pointing Time shar
38. ions of any one band are smaller than 1 and offsets between bands have been mea sured to be below 2 Checking the pointing focus and receiver alignment is the responsibility of the observers use a planet for alignment checks Sys tematic up to 0 4 mm differences between the foci of various receivers can occasionally occur In such a case the foci should be carefully monitored and a compromise value be chosen Not doing so may result in broadened and distorted beams 9 Wobbling Secondary Beam throw is lt 240 depending on wobbling frequency At 2 Hz the maximum throw is 90 Standard phase duration 2 sec for spectral line observations 0 26 sec for continuum observa tions Unnecessarily large wobbler throws should be avoided since they introduce a loss of gain partic ularly at the higher frequencies and imply a loss of observing efficiency more dead time Beam widths and Efficiencies See the summary of telescope parameters on the for the current efficiencies be tween 70 and 270 GHz and the predictions for the 8 CALL FOR OBSERVING PROPOSALS ON THE 30M TELESCOPE 345 GHz 0 9 mm band Backends The following four spectral line backends are avail able which can be individually connected to any EMIR band and to HERA VESPA the versatile spectrometric and po larimetric array can be connected either to HERA or to a subset of 4 single pixel re ceivers or to a pair of single pixel receiv
39. ls Bandwidth Mode MHz MHz 0 039 1 x 512 20 SSB 0 078 1 x 512 40 SSB 0 156 2 x 256 80 DSB 0 312 1 x 256 80 SSB 0 625 2 x 128 160 DSB 1 250 1 x 128 160 SSB 2 500 2 x 64 320 DSB Note that 5 of the passband is lost at the end of each subband The 8 units can be independently connected to the first or the second correlator en try as selected by the IF processor see above Please note that the center frequency is expressed in the frequency range seen by the correlator i e 100 to 1100 MHz The correspondence to the sky frequency depends on the parts of the 3 6 GHz band width which have been selected as correlator inputs and on the selected receiver side band LSB or USB ASTRO The software ASTRO can be used to simulate the receiver correlator configuration Astronomers are urged to download the most recent version of GILDAS atl IRAMFR GILDAS to prepare their pro posals The previous LINE command has been replaced by several new commands see internal help the following description applies to the current receiver system The behavior of the LINE command can be changed by the SET PDBI 1995 2000 2006 com mand that selects the PdBI frontend backend sta tus corresponding to years 1995 old receivers 500 MHz bandwidth 2000 580 MHz bandwidth 2006 new receivers and new IF processor 3 6 GHz band width Default is 2006 LINE receiver tuning NARROW selection of the narrow band correlator inputs
40. m fr if you are interested in this o Observers who wish to finish data reduction at their home institute should obtain the most re cent version of CLIC Because differences be tween CLIC versions may potentially result in imaging errors if new data are reduced with an old package we advise observers having a copy of CLIC to take special care in main taining it up to date The newer versions are in general downward compatible with the pre vious releases The recent upgrades of CLIC implied however many modifications for which backward compatibility with old PdBI receiver data is not yet fully established To calibrate data obtained with the old receiver system up to September 2006 we therefore recom mend to use the January 2007 version of CLIC This CLIC version is included in the general GILDAS package accessible as clicO7 Technical pre screening All proposals will be reviewed for technical feasibil ity in parallel to being sent to the members of the program committee Please help in this task by sub mitting technically precise proposals Note that your proposal must be complete and exact the source position and velocity as well as the requested fre quency setup must be correctly given Non standard observations If you plan to execute a non standard program please contact the Interferometer Science Opera tions Group sog iram fr to discuss the feasibility Documentation The documentation for the
41. n site gt 10 dB The default rejection for all EMIR receivers is 13dB Velocity scales It is common practice at radio observatories to cor rect the frequency of an observation for the strongly time variable velocity of the Observatory with re spect to the solar system barycenter This guaran tees that lines observed near the Doppler tracked frequency usually the band center always have the correct barycentric velocity independent of the time of observation However the effect of the Obser vatory s motion on the velocity scale which affects most the velocity channels farthest away from the Doppler tracked frequency is usually ignored This effect which is of the order of 1074 cannot be neglected anymore if large bandwidths are used as with EMIR The worst case occurs with band E090 where channels as far away as 20 GHz need to be considered if a velocity channel in one of the side bands is Doppler tracked In unfavorable but nev ertheless frequent cases target source not too far from the ecliptic like the Galactic center errors of up to 2 MHz occur Since the magnitude of the error changes with time narrow spectral lines may be broadened after a few hours of observation and spectra taken at different epochs may not align in frequency HERA A full description of HERA HEterodyne Receiver Array and its observing modes is given in the Here we only give a short summary The 9 dual polarization pixels are arr
42. ng is also possible to map larger areas Under many circumstances maps may be co added to reach lower noise levels If maps with an rms lt 1 mJy are proposed the proposers should contact Robert Zylka zylka iram fr The bolometers are used with the wobbling sec ondary mirror wobbling at a rate of 2 Hz The orientation of the beams on the sky changes with hour angle due to parallactic and Nasmyth rota tions as the array is fixed in Nasmyth coordinates and the wobbler direction is fixed with respect to azimuth during a scan Bolometer proposals partic ipating in the pool have their observations maps and ONOFFs pre reduced by a data quality mon itor which runs scripts in MOPSIC This package complete with all necessary scripts is also installed for off line data analysis in Granada and Greno ble It is also available for distribution from the GILDAS web pagel Bolometer proposals will be pooled together like in previous semesters along with suitable heterodyne proposals as long as the respective PIs agree The web based time estimator handles well the usual bolometer observing modes and its use is again strongly recommended The time estimator uses rather precise estimates of the various overheads which will be applied to all bolometer proposals If exceptionally low noise levels are requested which may be reachable only in a perfectly stable quasi winter atmosphere the proposers must clearly say so in their time estimate p
43. r The VLBI ter minal is also fed from this processor Calibration Issues EMIR has its own calibration system The exter nal warm optics provides ambient temperature loads and mirrors reflecting the beams back onto the 15 K stage of the cryostat This system is expected to be very reliable and constant over time Absolute cali bration accuracy will be better than 10 with EMIR when all details are well settled Bands E150 and E230 have backshort tuned 1 The 4 channels of 8 GHz width available from E090 are rearranged by the IF switch box into 4 pairs of inner and outer 4 GHz wide channels single sideband mixers DSB tuning is not possi ble but sidebands USB or LSB may be selectable within limitations The image rejection is better than 10 dB for all frequencies On site measure ments of the rejection is not longer straightforward for these mixers since the Martin Puplett interfer ometers are not available anymore for sideband sep aration As the optimum way of calibrating the im age rejection is still under study users who propose observations which rely on an enhanced accuracy of calibration of image gains should mention this re quest in the proposal Bands E090 and E330 have tunerless sideband separation mixers allowing simultaneous observa tions of both sidebands in separate IF bands These mixers have been characterized in the laboratory for their image rejection and are expected to have the same performance o
44. rmative technical overview of the architecture is available at URI A Fast Fourier Transform Spectrometer FTS is being implemented as a new backend for use with the heterodyne receivers It consists of a series of FTS modules purchased from Radiometer Physics Each module is currently configured to dig itize an IF band of 1 5 GHz width and to give more 4 URL addresses preceded by two dots are relative to http www iram fr than 8000 spectral channels In the initial version operational in the coming winter semester two FTS blocks will be available where each block combines 3 modules to give a contiguous 4 GHz band with a spacing between channels of 195 kHz Each block can be connected to any of the 4 GHz IF signals of EMIR in parallel to the 4 MHz filterbank Work is in progress 1 to increase the FTS band width up to 32 GHz at 195 kHz resolution and 2 to provide a higher spectral resolution of 50 kHz If installation and commissioning work out as planned we expect that the expanded FTS features become available during the summer semester Observers should make it clear in their proposals if the ex panded features are essential in reaching their goals A more detailed description of the expanded FTS backend is given in the IRAM Newsletter of Febru ary 2011 Polarimetry Polarimetric observations can be made using a dual polarization band of EMIR connected to VESPA in a setup designated as XPOL The technical aspec
45. rom 16 inputsE The box can handle all plausible single band observations as well as the band com binations indicated in Tab A full list of possible switch settings is available on the EMIR home page in Granada The selected 4 output channels are sent via the IF cables to a backend distribution unit which pro vides copies of these 4 channels to a range of backend processors which then prepare the IF signals for dis tribution to the spectrometers The following three backend processors feed the 4 GHz wide IF channels to the backends gt The WILMA processor rearranges the four incoming 4 GHz wide IF channels into 16 chan nels of 1 GHz width which can be processed by 16 WILMA autocorrelator units Since each unit provides 512 spectral channels of 2 MHz sufficient backend power is available at this low spectral resolution for full coverage of the 4 x 4 GHz bottleneck gt The 4 MHz processor rearranges any two in coming 4 GHz wide IF channels into 8 slices of 1 GHz width for processing in 8 units of the 4 MHz filter bank 2 x 4 GHz of EMIR bandwidth are thus covered at 4 MHz resolution gt The narrow band backends processor prepares the 4 incoming IF channels for input into VESPA Only the central part of the 4 GHz IF channels is accessible to this backend Inside the central part 640 MHz VESPA can be con figured as before Note however that VESPA bands cannot be moved outside the 250 MHz range around the band cente
46. six Bure antennas are now equipped with aluminum reflectors Band 4 receivers and 3rd generation LO system Band 4 mixers covering the frequency range from 277 to 371 GHz have been installed last summer on the remaining 4 antennas antennas 4 and 5 were al ready equipped in 2009 The new 0 8mm band was commissioned during the Christmas period and first science verification as well as regular user requested observations have been successfully obtained since the beginning of this year The performance of the new band 4 receivers meets our highest expecta tions The mixer for the vertical polarization on an tenna 1 suffers however from a hardware problem and will therefore be replaced during the upcom ing antenna maintenance period Observations in the 0 8mm band are very demanding in terms of at mospheric transparency and stability and therefore are restricted to the best winter weather conditions A new this is the 3rd generation LO system was installed on Plateau de Bure during September and is routinely used since the beginning of October Weather conditions and observing The current winter semester so far was affected by variable weather conditions with periods of excel lent atmospheric stability and transparency at the beginning of November and January as well as dur ing the second half of January but with very poor weather during most of December Bure entered into the winter observing period with the array in the C
47. ts of XPOL are described in de tail for the previous generation of heterodyne re ceivers Thum et al 3 together with its ob serving capabilities and limitations The adapta tion to EMIR is described in a http www iram es TRAMES mainWiki CalibrationPapers action 2010 polarimetry v3 pdf Most notably XPOL gen erates simultaneous spectra of all 4 Stokes param eters The following combinations of spectral res olution kHz and bandwidth MHz are available 40 120 80 240 and 320 480 More complex observ ing modes where VESPA is split into two bands are also possible see the VESPA user guide IQ XPOL has been tested for the EMIR bands E 090 and E230 see the XPOL profits from the improved performance of EMIR in sev eral respects smaller or negligible phase drifts small and stable offsets between the two polarizations and negligible decorrelation losses Polarized sidelobes albeit smaller than typically observed with the previous receivers are still com plicating observations of extended sources Current evidence indicates that the rotation of the sidelobes with elevation is more complicated than with the previous receivers possibly due to the off axis in stallation of EMIR Proposals for observation of ex tended sources should demonstrate that their ob servations are feasible in the presence of the known sidelobes Proposals for polarimetric observations may be Organizational aspects submitted for EMIR ban
48. tted Investigators who wish to check the status of their project may consult the interferometer schedule on the Web at IRAMFR PDB ongoing htm This page is updated daily Jan Martin WINTERS Call for Observing Proposals on the Plateau de Bure Interfero meter Important information Please note that the proposal sty file and the LaTeX template have been changed considerably In fact we have different template files for the two telescopes prop pdb tex and prop 30m tex Please make sure to use the current version of these files and the common LaTeX style file proposal sty All three files may be down loaded from the IRAM web pages at URL GENERAL submission proposal html Do not change the font type or size and do not manipu late the style file In case of problems contact the IRAM scientific secretary e mail berjaud iram fr 5from here on we give only relative URL addresses In the absolute address the leading two dots should be replaced by http www iram fr 12 Proposals using older versions of the style or tem plate files will not be accepted Conditions for the next summer pe riod In contrast to the previous years no major techni cal upgrades are foreseen during the upcoming sum mer period 2011 During the regular antenna main tenance period scientific observations will mostly be carried out with the five element array We plan to start the maintenance at the latest by the end of May
49. z 20 40 40 80 80 160 320 320 1250 640 The maximum bandwidth can actu ally be split into two individual bands for each of the 18 detectors at most resolutions These individual bands can be shifted separately up to 250 MHz offsets from the sky frequency see also the sections on backends below gt a low spectral resolution 4 MHz channel spac ing filter spectrometer covering the full IF bandwidth of 1 GHz Nine units one per HERA pixel are available Note that only one polar ization of the full array is thus connectable to this filter bank gt WILMA with a 1 GHz wide band for each of the 18 detectors The bands have 512 spectral channels spaced out by 2 MHz HERA is operational in two basic spectroscopic observing modes i raster map of areas typically not smaller than 1 in position wobbler or fre quency switching modes and ii on the fly maps of moderate size typically 2 10 Extragalac tic proposals should take into account the current 2 As long as the NCS raster command is not operational the raster pattern has to be traced out with the help of a SIC loop limitations of OTF line maps as described in the HERA User Manual due to baseline instabilities induced by residual calibration errors HERA pro posers should use the web based For details about observing with HERA consult the User Manual The HERA project scientist Karl Schuster schuster iram fr or Manuel Gonzalez gonzal
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