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Indian Summer Students at CERN 2014

1. Fig 1 Raspberry Pi Fig 2 Arduino and sensors 16 Reception Code The code in RPi for reception is written in C It reads from RF receiver and stores a particular number of values say 516 in an array known as buffer This buffer is then analyzed for information The algorithm for identifying data in buffer is Search for the key of sensor Skip the bits having data and parity bit Check if the key sent at the end of message is available If both ending and starting key are detected then we analyze the bits in between Calculate the value of the data and check if it is even or odd Now compare the result obtained above with parity bit AE ee ee If the two match then the code declares that data has been received Storing data All the data obtained in the previous section is saved in a text file having the name date _cleanroom txt where date is the actual date of that day in the format yyyymmdd Display of data graphs All the data received is displayed on an LCD TV in real time For this we are using Gnuplot It is a portable command line driven graphing utility for Linux OS 2 MS Windows OSX VMS and many other platforms Gnuplot can generate two and three dimensional plots of functions data and data fits On the screen we display graphs of temperature pressure and humidity sensor values along with the last value received We display the present time as well The display looks like Fig 3 a i
2. Input station for pressure leak test 30 Post this a manual spacer test is done to ensure all spacers are in place and rigid by placing a Spacer map on the gap and pressuring spacer points to check for high pressure deviations In addition physical inspections are conducted to check for unnaturally large bubbles broken coatings and other apparent shortcomings The gaps tested above are assembled in a gap stand where their surfaces are put to high voltage The voltage values vary from 3 to 10 kV over the 2 mm gap spacing The tests check for leakage current for the applied voltages in two ways One part checks the leakage for a range of voltage values and the next step is to check leakage at a high voltage value maintained for a long time Above Gap stand for electrical testing Below Scatter plot Voltage vs Leakage Current Gap RE4 3 B123 Bus i na Laga Lato au uan pres U 1 5 au Tn um U min ii mm UO 31 Post assembly the completed RPC chambers are assembled in the cosmic stand which uses cosmic muons passing through the lab to conduct real time tests on the detectors The cosmic stand test runs for three to our days and cosmic muon paths are tracked with performance recorded and evaluated in real time This test is complete with gas inputs and high voltage applied It is a combined test of the final product Above Cosmic Stand at CERN Below Final assembled chambers 32 Project Report
3. Test 3 PULSE GENERATOR TEST TO CHECK AMPLIFICATION FACTORS This is the first and only time we have to use an input Step 1 Connect a signal cable from the signal generator to the input terminal of the PASA The parameters for the input signal from the generator are as follows Rise time 2 5 ns to 4 ns Fall time 7 ns to 10 ns Pulse width or duration to be adjusted according to waveform from PM Amplitude 100 mV The same tests as specified in Test 2 have to be repeated Fig 6 The Pulse Generator used to generate the signal of given parameters for aforementioned test Test 4 LONG TERM TEST This test is mainly implemented in order to see what the effect of time and temperature is on the PASAs especially on the amplification factors obtained from the PASA For each of the PASA the result has to be checked after an interval of 1 hour For the purpose of the test 8 PASAs were chosen at random and the amplification factors of both the non amplifying and the amplifying were measured at an interval of 1 hours for about 3 hours giving 3 sets of readings for each of the 8 PASAs III RESULTS For the Test 1 we simply needed to plug ina single PASA in the back plane and plug in the P6V and MIOV and GND m the appropriate holes in the back plane as shown in diagram 4 The results including the reference values are represented in tabular format Reference values Rgl 5V Rg2 5V Reg1 1 5V Reg2
4. 8 5V NEW PASA SI No Rg1 Rg2 Regi Reg2 00 28831 e1 0001 4 982 4 997 1 504 8 516 00 28831 e 1 0002 5 0044 4 9908 1 4991 8 532 00 28831 e1 0003 4 9779 5 0156 1 5044 8 538 00 28831 e 1 0004 5 0484 5 02 1 5026 8 49 00 28831 e 1 0005 5 5 0197 1 5017 8 47 00 28831 e 1 0006 5 013 4 9992 1 4997 8 516 00 28831 e 1 0007 5 0092 4 9933 1 5008 8 537 00 28831 e 1 0008 4 9525 4 9963 1 5001 8 486 00 28831 e 1 0009 4 9611 5 0045 1 5034 8 5 00 28831 e1 00010 5 0007 5 0265 1 5022 8 554 00 28831 e1 00011 4 9801 4 9754 1 4997 8 551 00 28831 e1 00012 5 031 5 02 1 5086 8 5556 00 28831 e1 00013 5 0078 4 9994 1 5002 8 484 00 28831 e1 00014 5 064 5 0399 1 5025 8 457 00 28831 e1 00015 5 0053 5 0066 1 4991 8 505 00 28831 e1 00016 5 0238 5 0012 1 5075 8 575 OLD PASA SI No PREAMP 000747767452000004 5 0047 5 0162 1 5038 8 548 PREAMP_000747767452000005 4 9993 5 0031 1 4945 8 486 PREAMP_000747767452000007 5 0072 5 0128 1 501 8 536 PREAMP_0007477674520000011 5 01 5 0184 1 5048 8 555 PREAMP_0007477674520000015 4 9003 5 0117 1 499 8 564 PREAMP_0007477674520000016 4 8731 5 0353 1 5025 8 566 PREAMP_0007477674520000037 5 0276 5 006 1 5046 8 511 PREAMP_0007477674520000042 4 9707 5 0034 1 4968 8 527 Table 1 Measured values of Voltage output for the 4 ICS as part of Test 1 for each PASA 80 For Test 2 this mainly deals with setting the offset levels for the amplified as well as the of the PASA by calibrating the pote
5. European Organization For Nuclear Research i eae oe A 7 s E naj Pd j lt 4 h l W 3 yf Z A Brief Report Summer Students From India 2014 European Organization for Nuclear Research 2 Indian Summer Students 2014 Internship Report Indian interns at CERN With Rolf Dieter Heuer Director General CERN amp Archana Sharma Physicist CERN Foreword What a great time to be a student of particle physics however young you are and from wherever in the world you may hail Every year CERN welcomes summer students people typically in the third year of their undergraduate studies who come here to work with our scientists at the cutting edge of human knowledge For the last few years students from our Member States have been joined by young people from other countries among them India and it s a pleasure for me to introduce the work of the 2014 cohort in this volume CERN is celebrating its 60 anniversary this year Sixty years of science for peace over which time we ve seen our membership grow from 12 countries to 21 and our user community expand to embrace over 100 nationalities India has long been among the most important of CERN s non European partners contributing to the intellectual life of the laboratory and also to our infrastructure through the provision of specialised magnets for the LHC to cite just one example Indian physicists were involved with the discov
6. Ml Constraints 1 GEM foil Applications Readout 2 GEM Foil 3 GEM Foil EM Frame 1 T t ae na m RR ee aa aa anang Outer Frame Drift Board 36 Further Proposed changes and discussions e The current model is still under discussion With the change in vfat and its arrangement cooling is most important concern Each of new Vfats generate 1 watt of heat and optical board 6 watt of heat So 1 24 6 30 watts So cooling system should be able to remove this amount of heat e The above project will be completed by 2015 and will be installed in CMS e GE2 1 project has started where one drift board will have chambers on both of its sides It is a complicated project which has just begun Conclusion Designing of Triple Gem based Super chambers will enhance the particle detection capabilities of CMS to a great extent Cooling is one of the important concerns since electronic chips and circuits are required to last during the long run have tried to include all my work and further progress of this project in this report showing all the necessary steps Acknowledgement take this opportunity to express my profound gratitude and deep regards to my guide Mr Antonio Conde Garcia for his exemplary guidance monitoring and constant encouragement throughout the course of this project The cooperation and guidance given by him time to time shall ca
7. 53 PROJECT REPORT CERN SUMMER STUDENT INTERNSHIP 2014 TITLE Assembling and testing of RPCs for muon upgrade in CMS NAME Pronoy Sebastian INSTITUTE NIT Calicut India SUPERVISOR Stefano Colafranceschi OVERVIEW Resistive Plate Chambers RPC are gaseous parallel plate detectors that combine good spatial resolution with a time resolution comparable to that of scintillators They are therefore well suited for fast space time particle tracking as required for the muon trigger at the LHC experiments An RPC consists of two parallel plates made out of phenolic resin bakelite with a bulk resistivity of 1010 1011 Ocm separated by a gas gap of a few millimeters The whole structure is made gas tight The outer surfaces of the resistive material are coated with conductive graphite paint to form the HV and ground electrodes The read out is performed by means of aluminum strips separated from the graphite coating by an insulating PET film The focal aim of the project was to assemble these parts and to test and rectify the defects observed CONSTRUCTION The Resistive plate chambers have the following constructional features 1 Aluminium Honey Comb The outermost part is the aluminium sheet which is made from aluminium wafers about mm thick and with the spacer honeycomb structure in between A material called PET is filled inside 2 Graphite Sheet 3 Copper strips on sheets of mylar 4 Bakelite with linseed
8. A leak rate of up to 0 3 millibar per second is accepted 20 Spacer Test The spacer test is done to make sure that the spacers that separate 4 Te the two layers within the gap are placed in the correct positions In AA e order to do this a template with the correct positions of the 91 mg Spacers is placed over the gap while it is pressurized Pressure is applied even further on the gap by pressing down on certain points While pressing a marked area there should be no significant change in the pressure due to the fact that there should be a spacer at that point However any other area while pressed down should show a considerable change in the pressure All marked areas are pressed down and if there is no significant change in pressure then it confirms that spacers are correctly positioned High Voltage Test This is the last element of the QC2 procedure The gaps are placed in a stand and a high voltage current is passed through them and leakage current is measured this process lasts 3 days There are two distinct parts to the test In the first the voltage is varied from 0 to 10 kilovolts and the leakage current is measured In the second part the voltage is kept constant at 6 kilovolts and 9 7 kilovolts and it is checked whether the leakage current is constant while voltage is constant 21 Chamber Construction Now that QC2 has been completed the gaps are removed from the stand and assembly of the chamb
9. Supervisor Jared Sturdy Jared Sturdy Antti Onnela Jeremie Merlin Stefano Colafranceschi Stefano Colafranceschi Stefano Colafranceschi Antonio Conde Garcia Jared Sturdy Anne Dabrowski Anne Dabrowski Stefano Colafranceschi Antonello Di Mauro Brian Dorney Giacomo Volpe Jean Pierre Revol Page No 14 18 25 25 33 38 44 44 54 59 64 71 11 Study and Development of GLIBv3 application framework in XDAQ system of CMS Sudeep Maity and Amal Roy B Tech students National Institute of Technology Goa Indian Summer Intern 2014 Cern Geneva Supervisor Jared Sturdy Abstract The project emphasizes on studying the role of GLIB in DAO system of CMS and developing a web user interface for accessing the internal readout registers of GLIB in XDAO Xdaggem environment Introduction The Gigabit link Interface boards GLIB is a field programmable gate array FPGA based system It is an evaluation platform and an easy entry point for users of high speed optical links in high energy physics experiments Its intended use ranges from optical link evaluation in the laboratory to control triggering and data acquisition from remote modules in beam or irradiation tests The GLIB is a double width Advanced Mezzanine Card AMC conceived to serve a small and simple system residing either inside a UTCA crate or on a bench with a link to a PC and it is based on a high performance Virtex 6 FPGA The GLIB can interface wit
10. mechanical shoebox along with a plugged in PASA on the back plane showing the blue connector pins to be tested Step 4 Plug in one PASA in the given orientation Step 5 Use a multimeter to check the following output voltages RG 1 R34 13414 Fig 3 A single PASA representing the respective ICs and the corresponding resistors capacitors used to measure the voltage for aforementioned test Test 2 BASE LINE OR OFFSET TEST Step 1 Connect the output terminal of the PASA at first the non amplifying output represented by PX2 and then the amplifying output represented by PX3 via the adapter to the input terminal of oscilloscope having a 50 ohm termination Step 2 Adjust the oscilloscope to measure DC Voltage Test 2a The Non Amplifying Output The first output will come without any amplification 1 e value of G almost equal to 1 Only potentiometer is required to be adjusted for the offset of the non amplifying output Fig 4 The circuit diagram of PASA corresponding to non amplifying output and the Potentiometer used to control the offset 19 Test 2b The Amplifying Output In this test we require two amplifiers in order to get a total amplification of around 10 in ideal case Hence 2 separate channels and 2 potentiometers are used for the test a A Fig 5 The circuit diagram of PASA corresponding to amplifying output and the Potentiometers used to control the offset
11. namely supply voltage V ground Gnd and output voltage Vsut The output signal is converted as PressMaxPositive VoutPressure 5 25 0 095 0 009 1 5 0 009 5 25 PressMaxNegative VoutPressure 4 75 0 095 0 009 1 5 0 009 4 75 PressMinPositive VoutPressure 5 25 0 095 0 009 1 5 0 009 5 25 PressMinNegative VoutPressure 4 75 0 095 0 009 1 5 0 009 4 75 Pressure PressMaxPositive PressMinPositive PressMaxNegative PressMinNegative 4 VoutPressure Vout step converter Humidity Sensor HIH 4000 This sensor provides the value of Relative Humidity RH It has three pins supply voltage V ground Gnd and output voltage Vout Humidity is affected by temperature So we consider temperature in our calculation of humidity from the observed voltage signal The mathematical equation is as follows Humidity 2 0 16 Z 5 0 0062 1 0546 0 00216 T Here T temperature observed by temperature sensor Vo Vout step converter Transmission The sensors used for measuring physical parameters are connected to Arduino Mega 2560 microcontroller The voltage signal from these sensors is received and converted to meaningful data by arduino using the equations mentioned in the previous section We use RF 433 MHz transmitter and receiver for transmitting information from sensors The delay between every two bits is 1 millisecond Message encoding The first step is to convert the decima
12. o o o N Ww A a JJ KONNY 0 _ NOISE RATE TEST USING THE DELAYED PULSE 1 nm z 2 1 Noise rate is high 2 Noise rate is low 69 CONCLUSION In this way the operating voltage threshold voltage the noise rate and the efficiency of each scintillators were calculated through these experiments And the scintillators were selected on the basis of their consistent output in terms of both photon counts and Efficiency and Noise rate calculated in the same conditions as required by the experiment setup for a Cosmic Muon Trigger System REFERENCES 1 Hamamatsu Release notes on Scintillators and Photomultiplier tubes 2 CERN CMS Database Muon tracking 3 Techniques for nuclear and particle Physics experiments by W R Leo Acknowledgements Firstly express my sincere gratitude to Dr Mrs Archana Sharma for selecting me so that could spend the best summer period of my life at CERN am really grateful to my home institute NIT Goa and Professor Dr B Reddy for permitting me to use this opportunity at CERN Geneva Switzerland to strengthen my career prospects thank my supervisor BRIAN DORNEY the person who made sure my internship is not very tiring or boring He asked me to create a catalog of the lab equipment so that understand them one by one which turned out to be very useful Even though he was busy with his own work he would make sure that don t have any trouble in my work and he
13. properly The wires are labeled in order to avoid confusion once the chamber is closed Two separate copper sheets are placed over the top gaps Next the cables are soldered to the readout strip and ground pins are soldered to the copper sheet After the soldering has been completed the cover can be placed and the chamber can be closed Next the patch panels for the gas pipes high voltage cables and the cooling circuit are mounted 22 The chamber undergoes one last leak test as an extra precaution The cooling circuit is the attached and flat cables are used to connect cables and the FEBs Finally an aluminum covering is attached to protect the cooling circuit and the chamber is completed Conclusion During my stay at CERN as an intern I had the opportunity to assist with the second quality control procedure and the assembly of the chambers However the process had not been completed yet QC3 has to be carried out next It repeats some of the elements from QC2 however the focus of the procedure is the use of a cosmic stand to evaluate detector performance parameters such as efficiency cluster size and noise Once this has been successfully completed the chamber is subjected to QC4 which involves powering up the chambers and monitoring their stability After this the chamber is finally ready to be installed 23 Acknowledgements Firstly would like to thank Mr Jianxin Cai for teaching me the aspects of his work c
14. Also we need less noise while the time resolution should be high For this RPC chambers with two gaps are usually used with common readout strip sheets Bakelite surfaces are also coated with linseed oil to reduce noise The gap configuration in one chamber is top wide top narrow and bottom gaps put in two layers with intervening copper readout sheets The front end boards are specially designed to transmit muon hit signals Analog signals from the strips are put through two discriminator circuits working in tandem One selects signals with levels above the threshold and the other detects the peak of the signal to discern the hit of the muon This processing is done by a customized ASIC chip with 8 channels one for each strip The resolution for determining the hits on the chambers is decided by the width of the strips In the endcaps the RPC chambers form four radially oriented discs with 36 chambers each CMS Muon Endcap System 29 TESTING The CMS muon labs were charged with assembling and testing the RPCs for RE4 The gaps and assembled chambers go through a series of physical electrical and run tests The bottom gaps as seen placed in a chamber m z t sq d gt pu m a TY The gas gaps have four nozzles and these are used to fill a test gas at 5 mbar and 15 mbar pressure to check for significant pressure deviations due to gas leakage The maximum deviations in a period of ten minutes are 0 4 mbar
15. CERN Summer Students Internship 2014 Name Mayank Gaurav g mayank3 gmail com Department of Mechanical Engineering National Institute of Technology Durgapur Supervisor Antonio Conde Garcia Title Designing of first full size Gem based Super Chamber Prototype for CMS Introduction The CMS muon system relies on three detector technologies Drift Tubes DT Cathode Strip Chambers CSC and Resistive Plate Chambers RPC The DT and CSC provide precision tracking functions and RPCs provide fast trigger During the CMS commissioning and construction several concerns were raised on whether RPCs would be able to sustain the very hostile environment that will be created due to release of huge amount of particles in high energy collisions it was decided not to instrument this area at all Gas Electron Multipliers GEMs are an interesting technology for the future upgrade of the forward region of the muon system since they can provide precision tracking and fast trigger information simultaneously moreover they can be designed with sufficiently fine segmentation to cope with high particle rates at LHC Aim of the Project This project covers the following topics in detail 1 Designing of long Super chambers with new Gem Frame 2 Introduction of new vfats and subsequent changes in Readout 3 Introduction and study on GEB 4 Introduction of flanges in the structure 33 New Long super chambers The above figure shows the
16. I would like to express my deepest appreciation to my supervisor Dr Antti Onnela who has attitude and the substance of genius He continually guided me and extended his ideas to solve the engineering problems Without his guidance and persistent help this research work would not have been possible I would like to express my profound gratitude to Dr Archana Sharma who opened world of physics for me motivated and guided me throughout the research work She explained and demonstrated the CMS detector especially Tracker which helped me to understand the significance of my role in Design and Analysis team CMS Tracker I am really grateful to all my colleagues Duccio Abbaneo Giovanni Bianchi Antonio Conde Garcia Jaakko Esala Alan Honma Mark Kovacs Stefano Martina Stefano Mersi Pierre Rose and Kamil Cichy who always guided me through their great ideas and experiences In the last I extremly grateful to CERN and IIT Indore whose joint effort gave me the best ever learning experience provided the inspiring atmosphere and a fantastic platform to prove and use my skill in best and effective manner 13 CERN Summer internship 2014 Report Wireless Environment Sensor By Eshan Yash Sharma IIT Indore India Supervisor Jeremie Merlin Introduction The aim of this project is to make a wireless environment monitor that can measure various environmental conditions like temperature pressure humidity and particle count This monitor
17. National Institute of Technology Durgapur Supervisor Dr Anne Dabrowski Design of a LabVIEW program to control a Oscilloscope and High Voltage Power Supply Measurement 1 Abstract In order to achieve the purpose of data collection save and analyze through the LabVIEW based platform this LabVIEW application is designed to control the oscilloscope by running it from a remote desktop which is not remotely connected from scope but have LabVIEW drivers installed It configures the scope to take data from channels when there is an external trigger It saves the data to csv format in a file The Program mainly control amplitude time scaling trigger delay and trigger position no of channels enable number of triggers to save from the front panel LabVIEW 2 INTRODUCTION CMS The Compact Muon Solenoid CMS is a general purpose detector at the Large Hadro Collider LHC It is designed to investigate a wide range of physics including the search for the Higgs boson extra dimensions and particles that could make up dark matter Although it has the same scientific goals as the ATLAS experiment it uses different technical solutions and a huge solenoid magnet to bend the path of particles from collision in the LHC LABVIEW AND NI VISA Alternative to the traditional instruments a virtual instrument is an effective way to fulfill the improving technical requirements The virtual instrument relying on computer technology highlight the
18. after 3 hours of filling manifested on Sep 2006 in M6RI just after transportation of cradle towards experimental site Second Leak was manifested on June 2010 when 2 pressure drops were noticed on 28 June 2010 18 00 and 29 June 2010 09 00 in M3RO after 2 years of not continuous operation the last being in 2008 Third Leak was noticed in October 2010 in vessel M3RO in same way as 1 Pressure trend showing drop sudden loss of C6Fi4 at 12 15 on June 2012 in M4RI radiator vessel The Impact of the problem are listed below v Not induced any Quantum Efficiency Losses in remaining photocathodes v Speculations are still going on inspecting the probable causes of leakage v Inspection of radiator trays using an endoscope has been done v A tightness check with Helium gas seems reasonable to examine the leakage but seems unrealistic at this moment Analysis So we examine the probable causes of leak failure The analysis below will just just speculate which may in turn be useful to preventively modify the detector operation and minimize further leakage The following reasons are listed l Cracking of Plates due to Thermal stress and Mechanical deformation Thermal Stress a E AT For Neoceram plate or Quartz plate a is in the range of 0 5x10 and E is in the range of 10 So chances 5 15 of material fracture by overloading of mechanical stress or buckling is rare as these ceramic materials have high Ultimate Tensile Streng
19. exchange the version information between the user and the VFAT using C code This code included all the html and JavaScript codes which were required to develop a web based graphical user interface which was wrapped under CGICC wrapper Xml files and make files were simultaneously developed for the build of the program This program was put on the server side and the user was made able to write the versions onto the VFAT registers and the written values were also read back from the registers to ensure its reliability 42 ACKNOWLEDGEMENT express my sincere and utmost thanks to Dr Archana Sharma who gave me this opportunity to be a part of a project associated with CMS collaboration CERN am deeply indebted to my supervisor Dr Jared T Sturdy for his excellent guidance and constant inspiration thank him for his patience to sit down with me and explain to me the architecture of the interface and staying throughout the entire debugging process He was very kind to answer all my doubts despite having a non computer engineering background real admiration for him would also like to thank my colleagues who were part of this group for all their support and encouragements throughout this program and making it a memorable experience And finally my parents for being there for me always 43 PROJECT REPORT OF SUMMER INTERNSHIP AT CERN 2014 Priya Prasad amp Nancy Nayak Department of Electronics and Communication Engineering
20. helping me to be a part of the group Heartfelt thanks to Archana Sharma Ma m for making my stay at CERN a productive and comfortable one She was there for our entire team whenever we needed her and took a lot of initiatives on her part to make our stay memorable Thanks are also due to my fellow CERN interns Mayank Rahul Sandipan Nancy and Priya Heartful thanks to Archana Sharma for being such a helpful guide at a place so far from home And last but not the least thanks to my parents without whom this would not have been possible NIT Goa MIT Manipal NIT Calicut
21. nearly constant phase Phase Phase 004 yu TRE Si Linear FI 2409 Tamga rj ye ici Linear FI 1 Temat F ATELE Lineer Fii SAH Tempe ci p HAHN Linger PIK 2 Tu y ata Linder FINSSLG Tema y C7007 ATZ y 20 LEG OJ p Ls A ye DAM dia we hl ha Odda pe ee 1 fsqrtiint 1 sortiintd Figure 6 Plot for alpha of constant temperature fills 61 Applying Phase Correction After getting the value of alpha for various fills from the above graph we apply phase correction to the above fills the fills with constant temperature Corrected Phase Phase Correcting Factor Correcting Factor Alpha 1 vint 1 vinto Some of the plots with corrected phase have been shown in Figure 7 amp 8 Corrected Phase amp Temperate vs Dete and Time faril E251 A ses agan Corrected Phase amp Temperature w Dalle and Time fortil 525 alpha 12 699257 Ap tee ATM Te Franc n Ay AM I WP JJ Mad in NY fo fl ayn za p ng i A hj ni M E f u a j ML Td HUG SS AU SOAL Ik IS mud EOS Cen nd Tir Figure 7 Corrected Phase plot for fill 2511 having Figure 8 Corrected Phase plot for fill 2516 having constant temperature constant temperature Applying Phase Correction to the fills with large temperature variation The same phase correction method used for the fills with constant temperature is now being applied to these fills and the plots are obtained Alpha is evaluated as linear trend from the begin
22. of Modules are neglected Deformation stresses due to thermal difference is neglected Ring is symmetrical along ZX plane Fig Properties of Foam and Skin Material are assumed to be orthotropic Simulations are performed considering Environment Temperature 22 C Carbon skins are modelled as skin shell to increase the calculation efficiency Results K13D2U Cyanate Ester UD 0 012 t 72 mm 1 As shown in Figl that point 1 2 and 3 are fixed one so the magnitude of deformation is less in nearby area of fixed points and rest of the part has not much significant amount of deformation The maximum deformation which is possible if acceleration due to gravity is working in the plane of the ring is 2 6 um which is absolutely in the safe limit And when acceleration due to gravity is considered to be out plane of plane then the possible maximum deformation is 8 um 2 The maximum von mises stress is produced is near the fixed points which is 533 MPa which is also under the same limit and if acceleration due to gravity is working out of plane of ring then maximum possible stress is 4 8 MPa M76 HexPly M76 UD MSSJ t 52 mm 1 If acceleration due to gravity is working in plane the maximum deformation possible is 11 mm while if g is working out of plane then maximum deformation possible is 115 mm which is of course away from the fixed point 2 The maximum von mises stress possible if acceleration due to gravity is working in pla
23. of fills may lead to wrong filling schemes and satellite bunches with offset collisions which in turn may affect data quality and luminous intensity It s therefore important for the experiments to be able to control the timing and monitor all these parameters with high precision The temperature and phase shift over a period of two years as observed by ATLAS experiment has been shown in Figure 1 59 su seyd mperature deg Te Figure 1 THE ANALYSIS Trends of some of the LHC fills The fills considered for this analysis have a stable beam time for at least one hour The first step was plotting the external temperature and the clock phase against date and time in order to select the reference fills between those with constant temperature Some of those fills are shown in figure 2 and 3 Fill 2701 mp ghee DELL CELM U s zi E Fl FRASE MSI W La i 5 ru Br LI hi gt eal H ILMIPLEAIUEL 1 u ee Nai EA PRO tte ZS NE B0LODTEI2 OSMA 05 M 2010100 BAMIN OBZ6 JCI2I668 CGOGZOLOAJ G a PEN NO DE AMI TINIE WTF AT TIKAF Figure 2 Temperature and Phase plot for fill 2635 Figure 3 Temperature and Phase plot for fill 2701 Finding out the constant temperature fills The fills with constant temperature the plots with temperature variation of not more than one degree Celsius are separated out from rest of the fills Some of those fills with constant temperatur
24. super chambers which were of equal size Now according to the new proposed model there will be 18 short and 18 long super chambers as shown below New Shot SC New Long SC So accordingly first model was proposed consisting of various parts lt gt Front Cover lt Outer Frame lt Cooling Pipes oF o Vfats Readout Board with GEM foils Drift Board 34 A brief description of parts e Vfats Very Forward Atlas and Totem VFAT chip It is a complex digital part for data formatting and transmission It resists radiations as well It sends the collected data finally to the Optical Board e Gas Pipe Transports the gas to be ionised e Readout Electrons multiplied and transferred into the induction gap are collected and detected on a patterned printed circuit board called Readout e Optical Board Sends the signal collected by the vfats to computer via optical cables e Spacers It was used earlier to separate the gem foils But new gem foils can be stretched e Cooling Pipe It is used for cooling vfats and optical board Generally one vfat generates 1 watt of heat So total of 24 watts Taking optical board and some extra total of 30 watts per chamber is assumed Removal of spacers and including new GEM Frame yellow EJ CATIA Vs R23 64 CE EJ stor SmatTesm Fie Edit Y Inset Tools Anelyze Window Help Autom Auto w Auto Auto Aut None iS uf gt gt 3 ea aN
25. which consist mostly of protons many arriving from deep space at very high energy About 10 000 muons reach every square meter of the earth s surface a minute these charged particles form as by products of cosmic rays colliding with molecules in the upper atmosphere Travelling at relativistic speeds muons can penetrate tens of meters into rocks and other matter before attenuating as a result of absorption or deflection by other atoms The muons have a half life of 2 2 microseconds At the speed of light this would give a range of only 660 m However at relativistic speeds the lifetime of the muon as we perceive it is much longer so the penetration is also much more 66 PRELIMINARY LAB TESTS There were a series of tests performed in order to verify the quality of the scintillators and the other functioning blocks in the setup The muons on striking the scintillator produced photons in the latter which was in turn connected head on to a PMT The PMT powered by a high voltage power supply converts the photon into electric signal by various steps as mentioned in the introductory note The output of the PMT goes into a Constant Fraction Discriminator CFD where the input pulse from the PMT is compared with a threshold voltage If the pulse voltage is more than the threshold then the CFD generates a digital high pulse which goes into the pulse counter e TESTNol The scintillators were completely insulated using black colored insulation tape
26. wi 2 eeQa Tuesday 29 07 14 15 56 47 Last value received at 11 29 16 Temperature 20 68 C received at 11 29 16 Pressure 257 02mBar 7 received at 11 29 16 Humidity 40 83 received at 11 29 16 Fig 3 Display 17 Summer Internship Report George Pius Perangatt 29 Aug 14 Aim The object of our project was to complete the required quality control procedure and assemble four resistive plate chambers RPCs Introduction During our stay at CERN the Large Hadron Collider was undergoing a long shutdown LS1 This allowed for certain upgrades to be implemented in the CM S experiment The upgrade required the installation of a fourth layer of RPC detectors in the compact muon solenoid thereby improving the muon tracking system and its ability to cope with higher luminosity We were assigned for the construction of four RPCs which would be needed in the installation of the new layer Procedure QC2 The first quality control procedure is called QC1 and is carried out by the manufacturer The second quality control procedure QC2 was carried out by us QC2 is similar to QC1 the purpose of it is to ensure the quality of the gaps and it and entails the following tests a visual inspection gas leak test spacer test and the measurement of dark current and stability over a period of 3 days Visual Inspection This test looks at the foll
27. 0 MHz in the experiment and the first level of the triggering system is used to filter out events of interest RPC layers form part of this triggering system covering the barrel and the endcap of the detector In accordance with the full recommendations of the CMS Technical Design Report during Long Shutdown I the process of adding a fourth layer RE4 in the muon detector system began The designated new layer has two rings of 36 chambers each to be placed in the endcap region 26 RESISTIVE PLATE CHAMBERS Resistive Plate Chambers are a type of gas detector that is used to detect charged particles by their effect of ionization of gases They were introduced by Santonico and Cardarelli in 1981 as a simpler alternative to spark chambers They consist of a pair of parallel plates made of a material of high resistivity with a gas filled within the spacing between the plates The parallel plates provide a uniform strong electric field due to high voltage applied across them within the spacing Readout strips X Insulator High resistivity electrode Graphite coating Gas gap High resistivity electrode Insulator Readout strips Y When a charged particle passes through the spacing the gas gets ionized The strong field propels the generated electrons towards the plates These free charge carriers lead to electron avalanches going on to deposit an electric discharge on the plate surface The plates ar
28. 2225 Fig 10 The Change in Amplification factors for both channels measured at an interval of 1 hour for 8 PASAs IV CONCLUSION AND DISCUSSION Test 1 i e the DC Test for the PASA produced conclusive results for all the 24 PASAs hence making sure that there is no problem with the internal circuitry of the PASAs The Power supply used for the tests is a simple Low Voltage supply from which 3 wires a P6V M10v and a GND has been fed directly to the appropriate sockets in the back plane This can give rise to some noise which may affect the test results for the PASA Since the PASA is very sensitive to the shape and characters of the pulse care has been taken to keep the pulse parameters same throughout the tests However in certain cases the shape of the pulse has changed and that may result in slight variations in the amplification factor as seen from the graphs A very striking feature is noted when the scale is changed on the scope in order to measure the amplitude As the scale is decreased it is seen that the amplitude also decreases slightly resulting in slight variations of gain factors In this experiment the scale for input channel was taken as 50 0 mV and for the output channels was taken to be 500 0 mv in the scope After performing the long term test it can be concluded that the entire PASA system should be allowed to warm up for about a period of 3 hours before any definite calculations can be done It i
29. E 08 K13D2U Cyanate Ester 5 00E 08 M55 200 4 00E 08 3 00E 08 T a rj p v fe w gt 2 3 g 0 00E 00 0 Temperature Celsius 12 Above is the graph of Equivalent Von Mises stress Vs Temperature While using K13D2U as carbon skin type with Airex as Foam Core when the in plane acceleration due to gravity is provided as loading the maximum possible equivalent stress varies linearly with respect to temperature It first decreases linearly until it crosses the environment temperature of 22 C then it increases linearly In case of K13D2U the maximum possible equivalent stress is 5460 MPa at 50 C while in case of M55 fibre the maximum possible stress is 3885 MPa whereas with T800 skin show the maximum possible stress is 4220 MPa This proves that K13D2U can withstand more stress as compared to other two carbon fibre skins So keeping all the aspects in mind no doubt K13D2U is the choice of skin material for this type of support structure keeping Airex 80 82 as foam core material but it is economically very much expensive so now it depend on how much deformation is acceptable and in this respect M55 fits best References CERN SharePoint 1 CMS Barrel PS Tracker Mass Calculation 2 Material Evaluation for CMS Barrel PS Tracker Support Rings 3 CMS Tracker Phase 2 Upgrade Analysis and Material Selection for CMS Tracker BPS Support Structure by A Verma ACKNOWLEDMENT
30. FPGA to clock synthesizer RW OxOB SPI command SPI interface configuration polarity phase frequency etc RW OxOC SPI_rxdata SPI interface data from clock synthesizer to FPGA RO OxOD DC settings I2C interface configuration bus select frequency etc RW OxOE RC command I2C interface transaction parameters slave address data to slave etc RW OxOF RC reply DC interface transaction reply transaction status data from slave etc RO Building a Web GUI for accessing the GLIB registers in XDAQ xdaqgem XDAQ XDAQ is a framework designed specifically for the development of distributed data acquisition systems It provides platform independent services tools for local and remote inter process communication configuration and control as well as technology independent data storage XDAQ is a middleware that eases the tasks of designing programming and managing data acquisition applications by providing a simple consistent and integrated distributed programming environment The framework builds upon industrial standards open protocols and libraries XDAQ in CMS control system CMS Control Systems Detector Control System Run Control System Java Web Technologies ao PVSS Siemens ETM SMI State Management Interface Low voltage High voltage Front end Front end Drivers Central DAQ Gas Magnet Electronics First Level Trigger amp High Level Trigger Farm Purpose The main idea behind the d
31. I also extend my thanks to all the faculty members of NIT Calicut for their external support and blessings 58 PROJECT REPORT CERN Summer Students Internship 2014 Name Rahul Sinha National Institute of Techno logy Durgapur Supervisors Antonello Di Mauro amp Ombretta Pinazza Title Analys LS of the LHC clock phase shift dependence on temperature and beam intens ity INTRODUCTION The LHC experiments rely on a proper and stable timing for the sampling of the detector signals and for the synchronization of the readout system The LHC timing is distributed and received at the experiments by a system which is common to all experiments The experiments have developed methods to monitor the LHC bunch timing based on beam pickups in order to assure the required stability of the experiment clock with respect to the bunch arrival times and the position of the interaction region The LHC clocks physically reach the location of the experiment via optical fibres buried up to 1m underground The phases of the received clocks at the experiments are not constant but they depend on temperature effects beam shape effects and also inherent jitter of the clock Optical fibres quartz dn dT gt 0 implies faster signal propagation during winter and slower during summer Expected overall seasonal drift for 20 degree Celsius variation is nearly 7 5ns Day night effect is nearly 200 ps In addition various operational problems during the preparation
32. PER EU YYY a a Yr FabLRk MMSY NORASKBYBU 46 BSdX SD PRN Semearvevene BWGQBL APS AE c Introduction of new vfats and its arrangement With several new proposals vfats pink were changed from rectangle to hexagon The arrangement was changed accordingly taking into the considerations Readout design slightly changed to be easily attached to outer frame and its outer dimensions changed keeping into account of the gem frame 35 Introduction of GEB e The new unit called geb is included in the design e It was specially designed to remove a large amount of cables that were emerging out in previous designs e Itis present in contact with readout e Size of GEB is smaller by 24mm compared to readout The figure below shows the arrangement of GEB with respect to readout lmm CMS VFAT3 Hybrid eee 6 5 mm 5 5 mm 1 mm Introduction of Flanges Flanges or ear shaped structures were introduced to attach readout to the geb It is present on sides of readout and geb and a total of six in number Exploded view of the model KU Front Cover UN LG DRIFT LG DRIFT 1 LG G10 FRAME LG G10 FRAME 1 wR LG ACTIVE SURFACE LG ACTIVE SURFACE 1 D gt LG ACTIVE SURFACE LG ACTIVE SURFACE 2 wA LG ACTIVE SURFACE LG ACTIVE SURFACE 3 Dj readout Main readout board wR BOX FRAME LONG BOX FRAME LONG 1 D FRT COVER SCWS LONG FRT COVER SCWS LONG 1 0 ces 1 GEB
33. PMT 4 EXPERIMENT DESIGN OF LABVIEW CONTROL SYSTEM FOR LECROY OSCILLOSCOPE Before explaining the design part it is very essential to know how to connect scope with PC without remote connection For the interface with Ethernet NI VISA application is used First the driver is installed Then go for Tools gt Measurement amp Automation Explorer gt Devices and _ Interfaces gt Network Devices gt Create New VISA TCP IP Resources Connect the device oscilloscope giving proper IP address and VISA name Tools gt Instrumentation gt Find instrument drivers gt If you are a user of National Instruments then you can connect the Lecroy wave runner 104mxi oscilloscope to the PC via internet network go to scan for instruments It will automatically detect the oscilloscope Then set visa resource name as given while creating new VISA TCP IP Resources In our program VISA Resource Name is BRM scope Configure all the channels with desired values set the file path enable channels which are required using boolean button given in front panel Set values for amplitude trigger position time base and number of events bins A The design of control block diagram The Program starts with a Case structure that helps us to enable the required channels LecroyWaveSeries lvlib Initiaize vi takes VISA resource name and establishes communication with the Device LecroyWaverunner 104MX1 A LecroyWaveSeries
34. Photons shows Pions Kaons and Protons A deviation from linearity in No Of Photons vs sin 6 will speculate some error FIGURE III 12 hpHMP_vs_mom hpHMP vs mom g Entries 63337 vo g Mean x 0 4451 9 Meany 0 9888 7E RMSy 0 5289 CJE p momentum of the track without considering the HMPID cluster range of GeV 5 aF Pup Momentum of the track taking into account the HIMPID cluster range of GeV 3 k Pr f i we of A E Normally slope 1 and Pyp p 20MeV 1 1 oE 11 l 11 L l 11 l Pa 0 1 2 3 4 T pHMP FIGURE IV Analysis The analysis have been made using a software called ROOT which is most widely used in HEP High Energy Physics The raw data from the experiments have been taken from the repository There are files in repository like root files one for each run and each file contains a TTree one for each object where TTREE is a root class that is implemented to store the information The processed data have been taken as input to the Different MACRO written in ROOT to generate plots to make the performance analysis of the seven RICH modules of the detector Plots have been made taking into consideration the various conditions existing in the detector after taking account of incidents like failure of some of the vessels of the radiator of particular RICH modules The plots that have been studied are YResNEGMEAN VI right mipChargeMPV VI left 6 OccupancyMEAN VI right Track selection for th
35. Quality hYResNEGMEAN 0 1001 1002 1003 1004 1005 Run number Plot showing the MEAN of Negative Y Residuals for every run 81773727 HH 1003 1004 1005 Run number Plot showing the MEAN of Occupancy for every run Assurance objects for a given level and a given detectors are stored in a ROOT file Checking of QA data objects this is done by comparing the parameters of the QA data with user defined reference QA data w For each run we retrieve the mean values of 1 X and Y residuals both positive and negative 2 mipCharge 3 Occupancy and plot them in one canvas to check the trend versus time vw If the values obtained are not within predefined limits then there are signs of error problem being at the detector level or at the reconstruction level in the codes 74 PRELIMINARY ANALYSIS OF LEAK IN HMPID DETECTOR SANDIPAN DAS Supervisor Giacomo Volpe NIT DURGAPUR 4TH YEAR Metallurgical and Materials Engineering Department Abstract A short review is provided where we careful report on the leakages of the C6F14 radiator vessel problem like v When were the leaks detected Fixations v Impact of the leakages on the Experimental Result 7 v Most Probable Speculations VA brief insight into the reasons Introduction There were 4 instances when the problem was reported v v v Liquid C6F14 inlets Pressure drop during first CeF 14 circulation test occurring only
36. Wicith Write Value Action System x EJ PASTEURA TC 220 TRIGGER CRATE Read Read x EJ TEnL 2194 14 namum e IEF sono mommo Bej 8 GBSORT 1 2718 x PAC 9 2726 c Ooo owas OO poo a l Bop wort ea DENTIFIER WORD i VERSION wom ji NN on m n m on no STATUS PLL UNLOCK BITS L Read Experience It has been a great experience to work with one of the sharpest minds of the world who work together as a team to discover the past present and future of the mankind These two months helped us academically to enrich ourselves with vast knowledge as well as improve ourselves to be part of a team work with others and share and learn many new things It also helped us in facing new challenges without fear of failure and step up in crucial situations and take responsibilities when required We hope we have utilized this golden opportunity to its maximum and hope to build up ourselves on these experiences Acknowledgement We would like to thank our mentor Mr Jared T Sturdy who guided us through the whole project and constantly helped us in the same Our heartfelt thanks to Dr Archana Sharma for giving us a golden opportunity to be part of this wonderful program We would also like to thank all our fellow members who were part of this group for all their support and encouragements throughout this program I also thank Dr G R C Reddy Director NIT Goa and Dr Venugopal Reddy Faculty in c
37. ation CONCLUSION The ideal trend of phase variation with temperature variation should have a slope of 6ps degree C From the above curve we can see most of the curves are nearly close to the ideal characteristics and the closest of all is the Fill 2493 which has been shown by red colour having a slope of 7 3ps degree C ACKNOWLEDGEMENT would like to thank my supervisors Antonello Di Mauro and Ombretta Pinazza for their constant support and guidance would like to thank Dr Archana Sharma for giving us this opportunity to be a part of the world s best research centre and for helping us out at any point of time and constantly motivating and inspiring us to work hard would also like to thank Dr N K Roy and Dr P Kumbhakar for providing me a chance to do an internship at a prestigious institution like CERN 63 PROJECT REPORT CERN SUMMER STUDENTS PROGRAMME 2014 SCINTILLATOR CALIBERATION FOR COSMIC MUON TRIGGER SYSTEM DONE BY SACHIN MATHEW VARGHESE SUPERVISOR BRIAN DORNEY NATIONAL INSTITUTE OF TECHNOLOGY GOA INDIA PLACE OF WORK TIF LAB BUILDING 186 CERN MEYRIN SITE GENEVA INTRODUCTION A Cosmic Muon Trigger System can be constructed using the scintillators as detectors and using the photomultiplier tube to receive the electric pulse The basic principle used here is that when the muons strike the scintillator it produces photons which in turn connected head on to a PMT The PMT converted the
38. ay in the KK channel the detection of charm The ALICE PID system has three detectors that participate in the particle identification with a full coverage of the central ALICE barrel TT 2 ADA ADC DETECTOR The ALICE detector is a multipurpose detector exploiting the unique physics potential of nucleus nucleus interactions at LHC energies ALICE is also studying proton proton collisions both as a comparison with lead lead collisions and in physics areas where ALICE is competitive with other LHC experiments The ALICE detector provides identification of hadrons electrons muons and photons produced in the collision of heavy nuclei as well as measurements of their trajectories momentum or energy in specific regions covered by the various subdetectors Diffraction is an important part of the non perturbative QCD studies It is also important in the tuning of Glauber models used to simulate PbPb and pPb collisions For this purpose the ALICE collaboration needs to install a simple scintillator hodoscope in the RB26 section of the LHC tunnel ALICE FORWARD DETECTOR is a small detector made of scintillation counters with optical fiber readout There will be no active element such as electronic equipment installed in the tunnel ALICE wishes to extend its diffraction program following its pioneering study at LHC for the first measurement of single and double diffraction cross sections at LHC by extending the detector efficie
39. cker the pixels and microstrips produce tiny electric signals that are amplified and detected The tracker employs sensors covering an area the size of a tennis court with 75 million separate electronic read out channels in the pixel detector there are some 6000 connections per square centimetre The CMS silicon tracker consists of 13 layers in the central region and 14 layers in the endcaps The innermost three layers up to 11 cm radius consist of 100x150 um pixels 66 million in total The next four layers up to 55 cm radius consist of 10 cm x 180 um silicon strips followed by the remaining six layers of 25 cm x 180 um strips out to a radius of 1 1 m There are 9 6 million strip channels in total 2 Strip sensors Strips 5 cm x 90 um Strips 5 cm x 90 um P 2 7W 92 cm2 active area Forr 40cm CQ Wee atom Pixel Strip sensors Strips 2 5 cm x 100 um Pixels 1 5 mm x 100 um P 50w 44 cm2 active area For r gt 20 cm ac in ate CZW About the same weight SUPPORT STRUCTURE CONSTRUCTION AND ASSEMBLY Tracker BPS has cylindrical layers each of which is individually made up of rings aligned in a line Each Ring has I or 2 cooling pipes and support plates for holding the 2S and PS modules in the required pattern To reduce the number of the modules while maintaining the same geometrically coverage area the proposed BPS geometry uses a tilted module arrangement Outer Barrel IE Ham AAAS SASALAR Tilte
40. d Inner Barrel a eens ee ee ee ie Os Oe Endcap 4 0 U m 25 module M PS Module To fulfil this requirement a support structure is designed which can offer a flexibility to glue the modules at per required angle In the current layout the modules closest to the centre are horizontal and supported by flat plates while those away from the centre are supported by Rings with modules tilted at angles ranging from 35 to 75 degree Ring is the basic structure of this support structure for PS and 2S Module Fixed Point Section Line Fixed Point Fixed Point Analysis of the structure is done with three different carbon skins K13D2U Vs M55 Vs T800 and keeping same foam core material Airex 80 82 Further deformations both in plane and out of plane are considered For the detailed analysis of CMS Tracker BPS is divided into three parts 1 1 Analysis of Ring neglecting the cooling arrangements triangular parts and support plates 10 considering two possible cases of loading in plane and out of plane gravitational acceleration 1 2 Analysis of Ring with triangular parts and support plates while considering both possible cases of loading in plane and out of plane gravitational acceleration 1 3 Thermal Analysis of Ring structure with support plate and triangular parts Modelling in ANSYS Workbench 15 Only self weight of ring is considered g 9 8066 m s2 Cooling pipes are neglected Weight
41. d in such a fashion that each one of them is parallel to one another and in a muon shower all of them should detect a muon crossing perpendicular its surface with a certain delay in nanosecond range and a photocurrent is generated Photocurrent is the current that flows through a photosensitive device such as a photodiode as the result of exposure to radiant power here photons from the scintillator In this test we take a collection of four scintillators and place them in parallel to one another on a cosmic stand We consider any three of them as reference to check the efficiency of the lone scintillator The logic behind the test is that the total particle count of the three reference scintillators combined is count T and the total particle counts of all the four scintillators is count Q and now the Error Count Q Count T These counts are subject to a counter being run for a period of 100 seconds at various voltages being supplied to the PMT ranging from 900V to 1650V We observe that when the power supplied to the PMT goes beyond 1500V the Efficiency vs Voltage supply curve reaches a plateau and stabilizes And the Error is given by the formulae Efficiency 1 Error These values are noted into a tabular form for each of the PMT If the Efficiency vs Voltage supply curve doesn t reach a plateau and stabilize then we reduce the threshold of the PMT under study and repeat the tests NOISE RATE TESTS The photocathode can be made of a variety o
42. d non amplifying outputs were monitored and the peak to peak amplitude values were recorded at a single instant directly from the oscilloscope The amplitude values of the output were then divided by the amplitude value of the input at that instant seen in a suitable scale in order to compute the gain of both these channels amplifying and non amplifying The graphical results of this test are shown below Amplification factor for Non Amplified Output of Various PASAs Amplification factor 0123456789101234136 1I9022295 81 e gee Amp eq Output of Various PASAs Amplification factor 01234567891012A344A316 1890222745 Fig 9 Amplification factor for a Non Amplified output b Amplified Output for Various PASA when the specific pulse is input For the TEST 4 LONG TERM TEST this test is performed as mentioned before in order to understand the effect of time on the amplification factor of the PASAs 8 PASAs were chosen at random and they were plugged in together in the back plane and the supply was switched on and the setup was left for an hour after which the reading was taken This was done for a period of 3 hours by taking readings at an interval of an hour The graphical representation of the variation is as follows 1 4 oa A F After 1 hour A AO AA F After 3 hours 0123456 7891012L3141316L 181907223 After 1 hour EM After 2 hours A After 3 hours 01234567 891412113414201
43. e highly resistive and this ensures that the deposited discharge does not dissipate immediately The spot at which the discharge is deposited remains blind for a certain time after deposition 27 The deposited charge leads to an induced charge outside the plate on regions covered by copper strips The induced charge on these copper strips generates electrical signals which are then passed on to the readout electronics for processing Formation of an electron avalanche upon ionization in the presence of a uniform electric field Readout electronics are interfaced to readout strips that register the location at which the induced charge appears thus helping in tracking muons The readout electronics contain discriminator circuits which send signals to link boards through copper cables Link boards then provide services for data compression and conversion to optical signals sent to the CMS counting room muen cathode A o a olo a B a a a a no Wires cathode induced charge M Ia cathode with strips 3 3 16 mm mm avalanche Se T ee plane cathode In our applications for the CMS the RPC gaps are made out of two parallel layers of bakelite They are filled a Freon gas mixture The surfaces are painted with graphite to form high voltage and ground electrodes on the two sides 28 For our purposes we need detection chambers that can withstand a high number of hits due to high event generation rate of collisions
44. e study that have been made are primary tracks by applying standard cuts hXResPOSMEAN 0 hXResNEGMEAN 0 e 3 o N N 2 2 o E E 0 1 2 3 3 1001 1002 1003 1004 1005 1001 1002 1003 1004 1005 Run number Run number Plot showing the MEAN of Positive Plot showing the MEAN of Negative X Residuals for every run X Residuals for every run FIGURE V 3 13 hYResPOSMEAN 0 3 gt Cumbe o Perak o N E Chamber 3 N Chamber 4 o Chambers m 2 amet o 2 o c ka c W 4 2 w po s zr 0 z 4 a E H e 1 _ 2 3 1001 1002 1003 1004 1005 Run number Plot showing the MEAN of Positive Y Residuals for every run FIGURE VI hmipChargeMPV_0 hOccupancyMEAN_0 5550r 35 Q H a ay w c a 5p00T S 3 p m 6 8 0 450 400 Nan e y LL 2 a S LZ L 350 3 W L LE p L 300 155 250 1001 1002 1003 1004 1005 1 1001 1002 Run number Plot showing the MOST PROBABLE VALUE of mipCharge for every run FIGURE VII Results and Discussion vw The quality assurance framework provides the means to assess the quality of the data at various level of Monte Carlo simulation and Monte Carlo and real data reconstruction The quality assurance is performed in 2 steps Creation of Quality Assurance data objects obligatory delivered from a root TH1 the
45. e variation have been shown in Figure 4 and 5 These plots allows us to study the dependence on the beam intensity having almost excluded the influence of the temperature variations 60 h z k H si E z E Had u z i i 3 2 k Wila Ha Val r ai Lr w a a i TRAST AT u Figure 4 Temperature and Phase plot for fill 2489 with Figure 5 Temperature and Phase plot for fill 2488 with constant temperature constant temperature Beam Intensity Dependence Scientific works ref Time of Flight CDF Il by Stephanie Menzemer propose the following model for the phase jitter dependency on the beam intensity l l Where phaseo is the phase of the fill at the beginning and into is the intensity of the fill at ph ph the beginning Now a graph was plotted between phase phaseo along y axis and 1 vint 1 Vinto along x axis Trend lines were added to the plots having zero intercept and the slope of those trend lines were determined from the plot The slope of the trend lines gave the values of alpha for different fills where alpha is the factor of proportionality between the two parts of the equation These values of alpha are then used as a model for the phases of the plots with constant temperature having nearly one degree variation The phase phaseO vs 1 vint 1 Vinto plot has been shown in Figure 6 Phase phaseQ vs 1 sgrtfint 1 sgrtlintO for fills with constant temperature and
46. ecifically for the development of distributed data acquisition systems It provides platform independent services tools for local and remote inter process communication configuration and control as well as technology independent data storage XDAQ is a middleware that eases the tasks of designing programming and managing data acquisition applications by providing a simple consistent and integrated distributed programming environment The framework builds upon industrial standards open protocols and libraries WHY DO WE NEED TO BUILD AN INTERFACE FOR XDAQGEM The main idea behind the development of the xdaqgem software is to provide a SOAP interface for communication between the VFAT and the computer It should provide the tools for exchanging the monitoring information between the applications tools facilitating the GUI development in case of the TS based on the AJAX technology Tools for remote logging monitoring the application state and many many others things REQUIREMENTS FOR MAKING AN INTERFACE O In order to develop the XDAQ application for controlling the given hardware component subsystem we must customize some framework classes define needed SOAP interface define GUI create the custom code for controlling and monitoring the hardware O LANGUAGES C Html and CSS JavaScript xml HOW DO WE MAKE AN INTERFACE To develop a basic web interface that interacts with the user and can be used to
47. er can now begin The following are the steps for assembly of the chamber First the chamber is opened and the bottom is lined with a copper sheet The bottom gap Is prepared by attaching plastic pipes ones that have already been cut and bent appropriately to the top right and bottom left gas inlets of the gap They must be heated first in order to attach them to the gas inlets The remaining inlets are blocked using more pieces of small plastic pipe half the pipe is filled with glue so once the other end is attached it serves as a cap that blocks the gas from escaping The copper sheet is cleaned and the gap can now be placed inside the chamber Afterwards the gap should be checked to make sure it is aligned correctly Once the alignment is correct the supports are fixed in and the gap surface is also cleaned Next a readout strip is cleaned and installed over the bottom gap The top gaps are prepared in a similar fashion as to the bottom gap Afterwards the top wide and top narrow gaps are placed carefully inside the chamber and the alignment is once again checked Once the top gaps are inside the chamber the two pairs of adjacent gas inlets must be connected via a U shaped plastic pipe in order for the two to function as one body when storing gas inside The plastic pipes are attached to the appropriate gas inlets and the remaining inlets are blocked The gaps are leak tested again within the chamber to make sure they are still functioning
48. ery of the Higgs boson a particle belonging to a family of particles that takes its name from the great Indian physicist Satyendra Nath Bose So important was his work that one physics professor famously quipped to a student You don t know who he was Half the particles in the universe obey him The discovery of the Higgs boson and the confirmation of the underlying Brout Englert Higgs mechanism makes it a great time to be involved with fundamental physics as we embark on a new chapter in humankind s understanding of the universe wish the Indian summer students whose work you can read here all the very best at the start of their careers and look forward to strengthening scientific and technical collaboration between CERN and India as we look forward to the next 60 years Rolf Dieter Heuer CERN Director General Indian Summer Students at CERN 2014 Amal Mayank Mrinalini Nabeel Rahul Sandipan Saswata Student 1 Amal Roy 2 Sudeep Maity 3 Ankit Verma 4 Eshan Yash Sharma 5 George Pius 6 Himanish Ganjoo 7 Nabeel Abdulla 8 Mayank Gaurav 9 Mrinalini 10 Nancy Nayak 11 Priya Prasad 12 Pronoy Sebastian 13 Rahul Sinha 14 Sachin Varghese 15 Sandipan Das 16 Saswata Das Contents Institute NIT Goa NIT Goa IIT Indore IIT Indore MIT Manipal BITS Pilani NIT Calicut NIT Durgapur DTU NIT Durgapur NIT Durgapur NIT Calicut NIT Durgapur NIT Goa NIT Durgapur NIT Durgapur
49. evelopment of the xdaqgem software is to provide a SOAP interface for communication between the glib and the computer It should provide the tools for exchanging the monitoring information between the applications tools facilitating the GUI development in case of the TS based on the AJAX technology Tools for remote logging monitoring the application state and many many others things Tasks Required In order to develop the XDAQ application for controlling the given hardware component subsystem we must customize some framework classes define needed SOAP interface define GUI create the custom code for controlling and monitoring the hardware Languages to be used C Html and CSS JavaScript xml Approach To develop a basic web interface that interacts with the user and can be used to exchange the version information between the user and the GLIB using C code This code included all the html and JavaScript codes which were required to develop a web based graphical user interface which was wrapped under CGICC wrapper Xml files and make files were simultaneously developed for the build of the program This program was put on the server side and the user was made able to write the versions onto the GLIB registers and the written values were also read back from the registers to ensure its reliability Figure Below is a sample idea of the web based reading and writing interface sem Focusllabel Tye
50. f materials with different properties Typically the materials have low work function and are therefore prone to thermionic emission causing noise and dark current from the PMTs To test for this we use a delay timer to delay a pulse from a PMT and check for the noise rate The signal from the PMT is taken to the CFD and then to the signal copier which gives three signals of same amplitude and delay as that of the input pulse Now one of these signals goes into the counter generating the total particle count that is count X Now the other one goes into a delay timer which delays this signal considerably in the range of micro seconds around 50us and now the input pulse to the delay timer and the output pulse from the delay timer goes into the guad coincidence logic board where these two signals are multiplied using an AND operation and this output goes to the pulse counter These signal counts the number of erroneous particle counts namely count Y This count is erroneous as the width of the pulse cannot be more that 50 us for that reason even in microseconds range Here the Noise Rate Count Y Count X And the Noise rate is calculated for various threshold voltages for the same PMT at the operating voltage with the highest efficiency until the noise rate is considerably minimized This test is repeated to calculate the threshold voltage of all the scintillators 68 EFFICIENCY TEST FOR PMT 1 EFFICIENCY VS OPERATING VOLTAGE o o o JJ O WO e
51. h PS Module support structure is concluded This Inner barrel part of the Phase 2 upgrade tracker contains PS Type Modules which are mounted in tilted trajectory The support structure is supposed to be homogenous made up of composites in order to provide the necessary strength so that the 2S and PS type of modules can be mounted The deformation in support structure should be as minimum as possible in order to place the module on predefined orientation Directional deformation in X Y and Z direction is measured to understand the pattern of deformation Further thermal behaviour of ring is analysed as the support structure is supposed to be subjected to the range of temperature from 50 to 50 C For detail report of this support structure find my detailed analysis report on CERN sharepoint where analysis results of each and every case are discussed in details Keywords CMS Tracker PS Module BPS INTRODUCTION The CMS tracker records the paths taken by charged particles by finding their positions at a number of key points The CMS tracker is made entirely of silicon the pixels at the very core of the detector and dealing with the highest intensity of particles and the silicon microstrip detectors that Ankit Kumar Verma Discipline of Mechanical Engineering School of Engineering Indian Institute of Technology Indore Madhya Pradesh 453446 India ankit kumar verma cern ch surround it As particles travel through the tra
52. h four SFP transceiver modules each operating at bi directional data rates of up to 6 5Gbps This performance matches comfortably the specifications of the GBT Versatile Link project with its targeted data rate of 4 8Gbps The GLIB I O capability can be further enhanced with two FPGA Mezzanine Cards FMCs The two high pin count FMC sockets each provide up to 80 user specific differential I O pairs directly connected to the FPGA as well as two differential clock inputs and two differential clock outputs The primary FMC also provides four optional 6 5Gbps transceiver lines thus allowing extending the high speed serial I O capability FMC Sockets AMC ACHA ZN E PILA Tala ra j Saver i 5 t Viren 61 pei XCBVLX1301 d cps SVE B P p i ioe gt 07 922 2 e a a PAR sm 1 GAJ gwi s Se RL pal ma LJ 5 we 8220 ii PY am ut A PR A Figure 1 Image of GLIB final prototype GLIBv3 The image above is of GLIBv3 board highlighting its major components 1 e the Virtex 6 FPGA the AMC connector the cage for 4 Small Form Factor Pluggable Plus SFP optical modules the FMC sockets the SRAM devices the socket for the GLIB user manual a Module Management Controller MMC mezzanine card and the 1000Base T interface cabled Gigabit Ethernet GLIB part of GEM Hardware e On detector electronics VFAT ASICs send data to an opto hybrid Which is re
53. harge CERN Summer Students Program for all their help in making this internship possible Finally I would like to thank all the CERN members for a giving a kind and lovely environment throughout the program and for helping us in all possible ways to make our stay a great experience for us REFERENCES 1 https espace cern ch project GBLIB public 2 https twiki cern ch twiki bin view XdaqWiki WebHome 3 https twiki cern ch twiki bin view CMSPublic WebHome 4 https twiki cern ch twiki bin view CMSPublic WorkBookCMSSW Framework 5 hhttps twiki cern ch twiki bin view MPGD GEMDA QOSoftwareFirmware 6 https twiki cern ch twiki bin view MPGD Electronics 7 P Vichoudis et al The Gigabit Link Interface Board GLIB a flexible system for the evaluation and use of GBT based optical links Project Report of Summer Internship CMS Tracker Upgrade CERN European Organisation for Nuclear Research 21 05 204 24 07 2014 Geneva Switzerland CMS TRACKER PHASE 2 UPGRADE ANALYSIS AND MATERIAL SELECTION FOR CMS TRACKER BPS SUPPORT STRUCTURE Antti Onnela Supervisor PH DT CMS CERN European Organisation for Nuclear Research Geneva Switzerland antti onnela cern ch ABSTRACT In this report analysis of the Ring which is the basic structural element of the proposed CMS Tracker BPS sub detector is done to ensure the sufficient stiffness and strength of a support Further material selection for CMS Tracker BPS Barrel wit
54. has been constructed for use at clean room of TIF CERN Our environment monitor senses the various parameters translates it into meaningful message and transmits it over radio frequency the other part of the monitor consists of a RF receiver connected to a small sized computer This small computer translates the received message into our language and then plots it on a TV screen Sensors We have used temperature pressure and humidity sensors These sensors send voltage signal in accordance with the physical conditions We have calibrated them by referring to their datasheets We use mathematical equations to convert their signal into decimal numbers The working of these sensors and their calibration are as follows Temperature sensor LM 335 According to its manufacturers it operates over a current range of 400UA to 5 mA When calibrated at 25 C it has typically less than 1 C error over a 100 C temperature range The conversion of sensor voltage into temperature is as follows To x Vread step converter 7 Vout Here T is temperature Vread is the voltage signal from sensor T is the temperature at which sensor is calibrated and Vout is the voltage output at T T In our case e 7T 25 C Vout 2 9815 V e Step converter 0 004882 14 Pressure sensor MPXA 6115A It is a piezoresistive monolithic signal conditioned silicon pressure sensor It has a range from 15 kPa to 115 kPa It has 8 pins out of which we use three
55. he respective scintillators Photomultiplier tubes PMTs for short members of the class of vacuum tubes and more specifically phototubes are extremely sensitive detectors of light in the ultraviolet visible and near infrared ranges of the electromagnetic spectrum These detectors multiply the current produced by incident light by as much as 100 million times in multiple dynode stages enabling for example individual photons to be detected when the incident flux of light is very low The combination of high gain low noise high frequency response and large area of collection has earned photomultipliers an essential place in nuclear and particle physics Photomuit Per tube PMT 65 Photomultiplier tubes typically utilize 1000 to 2000 volts to accelerate electrons within the chain of dynodes The most negative voltage is connected to the cathode and the most positive voltage is connected to the anode Negative high voltage supplies with the positive terminal grounded are preferred because this configuration enables the photocurrent to be measured at the low voltage side of the circuit for amplification by subsequent electronic circuits operating at low voltage Voltages are distributed to the dynodes by a resistive voltage divider although variations such as active designs with transistors or diodes are possible The divider design which influences frequency response or rise time can be selected to suit varying applicat
56. hydrostatic load 4 Initial Detachment of Glue Fitting Tray Excessive tray sliding in fixations may detach CoF14 inlet fitting and thus the problem of leakage is severe Though the possibility of such an occurrence looks remote as extensive care is taken while fixing the trays by the experts and technicians 5 Ageing of Glue Most prevalent reason of leakage of radiators is AGEING of glue ARALDITE possibly by circulation of C6F14 perfluorohexane The main issue is there is no possibility for chemical analysis for C6F 14 at tray outlet because of liquid mix up with the bulk in the reservoir and the detector ca not be taken out before 2019 SO whatever we hypothesize will only be limited to ourselves this cannot be applied or even minimized until the radiators are taken out An adhesive s strength is measured by COHESION and ADHESION which in turn is dependent on Curing Time Curing Temperature and Viscosity Curing Time is the time taken by an adhesive to cure fully If sufficient time is not given to the adhesive it will not cure fully Typically higher curing temperatures produce a more complete reaction with a greater degree of crosslinking than lower temperature Alternatively increasing the length of curing time does not always yield the same degree of cross linking as curing at high temperature Curing at a high temperature will provide sufficient kinetic energy to quickly initiate chemical reaction to form crosslinks faster at even the mos
57. ime say tl Now owing to the bell shaped nature of the curve plotted between the total charge and the number of particles possessing it there is a particular instant say t2 where the number of particles are same which carry different amount of charges Hence they should be designates as two separate events However the detector will 78 detect the two separate events as same Hence we need to use an amplifier so that it amplifies the signal in such a way that the events occur at the same time that is it brings tl and t2 closer to one another Hence PASA is an important part of the system II TESTING PROCEDURE EQUIPMENTS REQUIRED FOR THE TESTS 1 PASA x 24 8 x 2 required for experiment 6 spare 2 Mechanical Shoe box 3 Low Voltage Power Supply CAEN SY2527 4 Power supply cable 5 Oscilloscope 6 Signal Generator 7 BNC to SMA adapters 8 Connecting wires both input and output side 9 Oscillator probe 10 Multimeter 11 Screw to operate the potentiometer of PASA Test 1 DC TEST FOR INNER POWER SUPPLY OF PASA Step 1 Disconnect all PASA from the mechanical shoe box Step 2 Connect the power supply cable between shoebox and low voltage power supply Step 3 Check the following voltages using a multimeter a Voltage between pin 9 and 10 should be M10V b Voltage between pin 7 and 8 should be P6V c Pin 6 5 2 and 1 should be at ground potential Fig 2 a The Circuit diagram for port J1 b The
58. ions Some instruments that use photomultipliers have provisions to vary the anode voltage to control the gain of the system WHAT ARE WE TRACKING The muon is an elementary particle similar to the electron with a unitary negative electric charge and a spin of 4 Together with the electron the tau and the three neutrinos it is classified as a lepton As is the case with other leptons the muon is not believed to have any sub structure at all i e is not thought to be composed of any simpler particles The muon is an unstable subatomic particle with a mean lifetime of 2 2 us This comparatively long decay life time the second longest known is due to being mediated by the weak interaction Muons have a mass of 105 7 MeV c which is about 200 times the mass of an electron Since the muon s interactions are very similar to those of the electron a muon can be thought of as a much heavier version of the electron Due to their greater mass muons are not as sharply accelerated when they encounter electromagnetic fields This allows muons of a given energy to penetrate far more deeply into matter than electrons since the deceleration of electrons and muons is primarily due to energy loss by the Bremsstrahlung mechanism As an example so called secondary muons generated by cosmic rays hitting the atmosphere can penetrate to the Earth s surface and even into deep mines On Earth most naturally occurring muons are created by cosmic rays
59. k the values and see if when a channel breaks down So we connected a desktop remotely with the desktop connected with SY4527 and took measurements as it is important to know the time of death of the channel We made trip current bit lesser than the maximum current This avoid encounter of any losses of channels 3 OBSERVATION For all the 24 channels Vmon takes value within 2800V to 2802 5V at different time instant 4 RESULT Hence the maximum percentage error is 2802 5 2800 2800 100 0 089 52 2800 2800 5 2801 2801 5 2802 2802 5 2803 Figure 4 Plot of channels vs Vmon Ji CONCLUSION The CAEN SY4527 high voltage power supply will be used to power Beam Halo Monitor and the acquisition program we have written will be used together with the device that makes the trigger to test systematically with cosmic rays muons all the 40 detector units of BHM 6 REFERENCES 1 Caen SY4527 Hardware evaluation test report C Moine A Guy https edms cern ch file 1244505 4 CAEN_SY4527 HW _ Evaluation doc 2 Caen SY4527 Control evaluation report B Farnham https edms cern ch file 1244505 4 CAEN_SY4527_Control_Evaluation docx 3 Caen V5 OPC server evaluation report B Farnham https edms cern ch file 1244505 4 CAEN V5 OPC Server Evaluation docx 4 Caen SY1527 and SY4527 comparative performance test report B Farnham https edms cern ch file 1244505 4 SY1527 SY4527 Comparative Performance Test docx
60. l data corresponding to the triggered time slot is trans erred to a second SRAM memory SRAM2 The LV1A latency is not expected to exceed 6 4s 256 clock periods Hence SRAM1 is dimensioned 256 by 128 SRAM2 contains only triggered data It is dimensioned to be 128 by 148 for data plus headers hence VFAT2 can store up to 128 triggered events of data for all channels at any one instant in time 39 VFAT2 will label the data with 3 headers These are the Bunch Crossing number BCN 12 bits Event number EN 8 bits and the chip Identification number ID 16 bits The BCN is generated by a 12 bit counter BC that increments every clock cycle and is reset to zero on receiving a BCO T1 command via LVDS The EN is generated by an 8 bit counter that increments for every LV1 It is also reset by a BCO command or the Clear signal Both counters are cyclic and return to zero at the end of the counter range As soon as SRAM2 contains data the Read cycle begins During the Read cycle a Data Formatting block streams out a binary data stream to the GOL The chip operates with a continuous write read operation without dead time VFAT part of GEM hardware On detector electronics VFAT ASICs send data to an opto hybrid Which is responsible for sending signals via the optical links to the front end electronics Gigabit Link Interface Boards are housed in a uTCA crate GLIBs communicate with the chamber electronics via optical fibers and sends data
61. l value into binary We have used a function in arduino for this purpose Next we have to solve the problem of incorrect transmission or noise Noise can be present due to several factors and we have to make the system capable of identifying the relevant signal For this we are using e Manchester coding e Parity bit e Sequential transmission of keys 15 Under Manchester coding bit 1 is expressed as 10 and bit O as 01 The parity bit is assigned the value 1 if the message is an even number and is assigned value O if the message is odd Lastly the message is sequentially transmitted as NEM ee ee HM As an example let s suppose the value of temperature is 22 12 C and the key for temperature sensor is 100 We multiply the sensor value by 100 to include the first two digits of decimal part The binary eguivalent of 100 is 01100100 and is 0000100010100100 for 2212 Parity bit for 2212 is 1 So the message transmitted will be 0110100101100101 01010101100101011001100101100101 1 0110100101100101 Thus the message length for 1 sensor data is 65 bits The data of the three sensors is sent one after the other with their respective keys and parity bit of message Reception at Raspberry Pi The transmitted signal is received by RF receiver operating at the same freguency as the emitter i e 433 MHz The receiver is connected to a Raspberry Pi which is a credit card size computer We use one of its 7 General Purpose Input Output pins GPIOs
62. ll gradually replace traditional instruments and the virtual instrument is bound to play its important role in more fields Virtual instrument front panel s controls are extremely similar to the traditional instrument panel s knobs switches buttons in the function and appearance This makes the front panel intuitive and image There are five Wavegraphs control the front panel the four Wavegraph Histogram CHx on the right side is used to display the Histogram of charge of the signal coming from PMT s The Wavegraph s function is very rich in the LabVIEW User can choose the line style color data points by Plot legend Using this feature we can adjust the instrument waveform s display color change the display of the data points The front panel also set up the buttons and controls In Front Panel we can give VISA Resource name File in which waveform data is to be saved Amplitude Position Time Delay Number of Events Vertical Coupling for each channel enable or disable channel Probe attenuation Vertical offset No of bins for histogram plot etc 47 gram CH2 ie LOWA SDA MISA resource name Penak I o Amplitude Time Base ag Postio Ej z l LabVIEW In 1 Block Diagram Figure 48 Histegram CHL histogram count um a C 2 Probe Attenuation 1 2 channeli Sa z J i 3 a gt y VISA resource name a8 M Vebas Coupling 0 A1M 2 z BRMSc
63. lvlib Configure Channel vi configures the common properties of the channels to acquire waveform Open Create Replace File takes the file path from the front panel and create or replace the file Gf already exists After each iteration of while loop waveform data is placed in that file Number of iteration of while loop is equal to number of events For every eventLecroyWaveSeries lvlib Read Multiple Waveforms vi waits for trigger and reads wave form data for all enabled channel whenever the trigger is received This waveform data enters to case structure if there is no error Inside the case structure there is a for loop In each iteration of for loop the waveform data is converted into two arrays one containing the voltage of waveform and other contains charge After the case structure a 2D array containing data of four channels is obtained which is exported to spreadsheet using Array to Spreadsheet String 46 Output of while loop is a 2D array event number of channels and it is transposed to get the following i Bvemt Bene Channell Channel2 Channel3 Channel4 Using Index Array we get separate 1D arrays containing data of all events of each channel and is plotted in Histogram B Front Panel Design Program front panel is a graphical user interface it is VI s virtual instrument panel Front panel is used to simulate the real instrumentation Function is similar to the traditional instrument panel Virtual instruments wi
64. ncy to smaller diffractive masses for single and double diffraction events and to increase the detection of gaps in the pseudorapidity distribution of particles produced in the collision for the study of central diffraction processes The ADA A side or positive Z coordinate and ADC C side or negative Z coordinate are two scintillator hodoscopes covering respectively pseudorapidity ranges of 4 7 lt q lt 6 3 and 7 0 lt n lt 4 8 With the ADA and ADC counters the sensitivity to diffractive masses will approach the diffraction threshold of about 1 08 GeV c corresponding to the sum of proton and pion masses The ADA and ADC counters will also provide level zero perhaps also level 1 trigger capabilities which is needed to extend the pseudorapidity coverage of the present Minimum Bias trigger used for particle multiplicity studies and for diffractive cross section measurements They will extend the pseudorapidity gap trigger crucial in the study of central diffraction where the physics reach is limited by statistics In addition the possibility of triggering on the charge deposition in the ADA and ADC detectors will provide an extended centrality trigger in both PbPb and pPb collisions studies 3 PASA CIRCUIT Fig 1 A single Pre Amplifier Shaper Circuit Board The reason we use the PASA is because the direct pulse we obtain from the PMT which is inverted in nature is directed by the detector setup at a t
65. ne is 4 4 MPa while if g is working out of plane then maximum possible von mises stress is 4 49 MPa M76 HexPly M76 UD M55J t 1 05 mm 1 If acceleration due to gravity is working in plane the maximum deformation possible is 114 mm while if g is working out of plane then maximum deformation possible is 1145 mm which is of course away from the fixed point 2 The maximum von mises stress possible if acceleration due to gravity is working in plane is 4 45 MPa while if g is working out of plane then maximum possible von mises stress is 4 45 MPa Comparison of Analysis Results Comparision between Material g in the plane of Ring Equivalent Von Mises Stress MM Total Deformation A o 20 do 60 80 100 120 BE M 6 t 1 05 mm M76 t 52 mm E cyanate Ester t 72 mm Comparision between Material g out of the plane of Ring Equivalent Von Mises Stress MPa E Total Deformation micrometre Ma en o 20 40 60 80 100 120 140 E M76 t 1 05 mm BM M76 t 52 mm E Cynate Ester t 72 mm It is clear from the graph while using the same core material Airex 80 82 performance of skins are different depending on their mechanical and thermal properties In case of the Cynate Ester the deformation is very less as compared to the other two skin used on the same core material but from economics point of view since the cost of Cynate Ester is much more as compared to those M76 ones further the deformation is much significant and obvio
66. ning of stable beam to the moment when the temperature variation reaches one degree Then this value of alpha is used for correction for the entire fill Corrected Phase amp temperature vs Date and Time for fill 249d Corrected Phase amp Temperature vs Dabe amd Time for fill 2453 r Dg Fan rated Piw ufa piia wectire Fast r acted Miia in phe r Figure 9 Corrected Phase plot for fill 2491 Figure 10 Corrected Phase plot for fill 2493 Plot of Phase Variation vs Temperature Variation Now a curve was plotted between phase variations for every one degree rise of temperature for different fills This plot was tried in order to see some relation between the temperature variation and phase variation The plot which was obtained has been shown in Figure 11 Phase Var vs Temp Var AQ m Fill 2495 a aa i AN 7594 ae p Fill 2621 Fill 2629 LF Fill 2635 FE p Eill Fifi gt pr yagua Linear Fill 2493 peta a v5 mogok linea Fil 2590 ae rs UB yr O04 Linear Fill 2624 wt ee Sea menage a gt R vEDOL linear Fil 7579 Fa a _ SF gt VE 0002 Linea Fill 2635 Pes a Pe al PP A Earls ova gage ce aia pee th y 0 00834 Linear Fill 2660 jl an i Tar 3 m 2 a x mi J EL 005 A areo o A ka x sA a e ah u pea ae p a MIEC czy NL a T eh 4 5 20 Temp Varn degree celsius Figure 11 Phase Variation vs Temperature Vari
67. ntiometer so as to orient the waveform seen on the oscilloscope with the non amplified output base line marker present on it For the non amplifying output calibrating the P2 is enough to correct the offset whereas in case of amplifying output we have to calibrate both potentiometers Pl and P3 in order to correct the offset The base line values for both amplifying and non amplifying outputs are represented in graphical form as follows Base Line value for Non Amplified Output mV E Base Line 1234567 89141114534 14902224 Base Line value of Amplified Output mV m Base Line 123456 8914111454 14902224 Fig 7 a Graphical representation of Base Line Value for Non Amplified Output b Graphical representation of Base Line Value for Amplified Output Test 3 is the only test in which we have to use an input pulse to the PASA The required input signal specifications have been mentioned before For practical purposes for the particular test we have use a pulse having the following parameters Amplitude High Level 0 000 mv Vpp Low Level 150 000 mV Vpp Rise time 5 0 ns Fall time 9 0 ns Pulse width 40 ns Frequency 20 000 kHz Nature Inverted ie a ara FA Miis 30 Jun 14 0859 5 m Fig 8 A typical shape of the inverted input pulse used for the aforementioned test The pulse was input and the output was connected to the oscilloscope via 50 ohm termination Both the amplifying an
68. ogy momentum spectra of identified particles particle correlations HBT and particle ratios ALICE has 18 detectors out of which HMPID High Momentum Particle Identification Detector is one which is used for the identification of particles with high momentum i e pions kaons and protons in the range of 1 5 GeV c Introduction The HMPID consists of seven modules in a calot like arrangement at the top of the ALICE set up The range of positive identification i e the range where the particles will emit Cherenkov light starts at different momenta for different particle masses For instance the lower limit for Kaon identification will be 0 7 GeVc and the lower limit for Proton identification will be 1 2 GeVc Cherenkov photons get emitted when a fast charged particle traverses the 15 mm thick layer of liquid Co6Fi4 perfluorohexane which in turn are detected by a photon counter which exploits the novel technology of a thin layer of CsI deposited onto the pad cathode of a multi wire proportional chamber MWPO The HMPID detector with its surface of about 12 m represents the largest scale application of this technique The Cherenkov photons refracts out of the liquid radiator and reaches the CsI coated pad cathode located at a suitable distance the proximity gap that allows the contribution of the geometrical aberration to the Cherenkov angle resolution to be reduced The electrons released by ionizing particles in the proximity gap filled
69. oil coating 5 6 HV connection to gap 10 FEB adapter boards 7 Gas mixture Freon li C4H10 SF6 11 Front end electronics 8 Plastic gas pipes 12 Output and Input Ports 9 Cables signal 54 Aluminium Honey Comb This ensures that the structure is light weight In RE 1 the whole structure 1s aluminium without the honeycomb because it 1s the detector nearest to the point of collision and must withstand high temperatures Graphite Sheet acts as the electrode for the RPC acts as cathode and anode on both sides Spacer To ensure that the spacing inside the RPC for the flow of gases remains even at 2 mm This ensures constant electric field within the air gap Spacers are 2mm thick and are placed at corners of a square grid of side 10 cm Bakelite with linseed oil coating functions as the insulator There are two plates Top plate and bottom plate The top plate is made of two sections whereas the bottom plate is a single piece The gas mixture flows between two bakelite plates Between two such structures the copper strips are placed Copper Strips when muon hits the chamber an electric discharge 1s produced within the bakelite plates because of the field and the gas This causes a change m concentration of electrons at the particular Strip and a current 1s passed on to the electronic control through the ports One such copper strip has 32 strips each of which is connected to the front end electronics arrangement through
70. oncerning RPCs at CERN and allowing me to assist would also like to thank Stefano Colafranceschi for his role as my supervisor and his continuous guidance that helped throughout my stay at CERN Last but not least would like to express my sincere gratitude to Dr Archana Sharma for providing me with this amazing opportunity which led to an invaluable experience 24 SUMMER INTERNSHIP JUNE JULY 2014 HIMANISH GANJOO BIRLA INSTITUTE OF TECHNOLOGY AND SCIENCE PILANI INDIA NABEEL M ABDULLAH NATIONAL INSTITUTE OF TECHNOLOGY KOZHIKODE INDIA SUPERVISOR STEFANO COLAFRANCHESCI OBJECTIVES ASSEMBLY AND TESTING OF RESISTIVE PLATE CHAMBERS FOR THE RE4 LAYER OF MUON DETECTORS FOR THE COMPACT MUON SOLENOID 25 MUON DETECTORS IN THE CMS The Compact Muon Solenoid experiment uses Resistive Plate Chambers as detectors and trigger systems for muons produced due to p p collisions in the Large hadron Collider Muons are relics of most important particle particle reactions for instance the Higgs boson candidate decays into four muons MUON CHAMBERS INNER TRACKER CRYSTAL ECAL fi i WEAR VERY rolwano CALORIMETER Total Weight 145001 Pe 0 E B Overall diameter 14 50m pa CZE Overall length 21 60m gt Magnetic field 4 Tesla In the CMS drift tubes and Cathode Strip Chambers are used to track muons and RPCs are used for triggering and reconstruction Events occur at the high rate of 4
71. only by a mono stable This logic 1 is written into the first of two SRAM SRAM1 All other channels that do not go over threshold record a logic O in SRAM1 This occurs in parallel for all 128 channels at 40MHz 38 At the same time a fast OR function can be used to set a flag which can immediately be used for creating a trigger It is foreseen to have up to eight programmable sectors which can be flagged with the fast OR in this way SRAMI SRAM2 p _ 256 128 128 148 Control Logic DataOut and Data Formatting DataVal LVDS LVDS DACo V Ts Ji T1 commands ms n RESETh sacl BCO LV1 RySync CalPulse Figure 2 Block diagram of the VFAT2 chip Triggering Function Within TOTEM VFAT2 will provide fast regional hit information to be included within the CMS First Level Trigger Channels are grouped together to form sectors A hit channel in a given sector will set an LVDS output assigned to that sector to a logic 1 The assignment of channels to sectors is programmable There are 8 LVDS sector outputs labelled S1 to S8 Not all LVDS outputs need be used and the number sectors used can selected between 1 2 4 and 8 Once the number of sectors have been chosen the channel assignment to the sector can be made with different options The options are determined by the requirements of the physics needed from VFATs used with the Roman Pots and VFATs used with the GEM detectors Tracking Function On receiving a LV1A signa
72. ope 050 2 Vertical Offset 0 0 V 2 L 0 i i i i do Amplitude Position Time Base Mupnbes of peruki bis 25E8 27568 368 BES 35E8 375 y E jo gt Joo 1000 z arzplitude 1 Begal Histogram CH2 histogram count a m G 2 4 Vertical Coupling 0 ALM file path use dialog J D50 2 3 Probe Attenuation 1 4 J E 3 2 Vertical Offset 0 0 V 1 0 1 1 l abn Vertical Coupling 0 ALM 3 8 2E 8 8 4E 8 8 6E 8 8 8E 8 9E fDimMm 1 1 amplitude Probe A don 1 3 Histogram CH3 histogram count lm J i 2 Vertical Offset 0 0 V 3 Jo E al u channe Vertical Coupling 0 ALM 4 DIM 1 d 1 1 1 1 1 1 Probe Attenuation 1 4 2 4E 8 2 6E 8 28E 8 3E 8 3 2E 8 34E ALA amplitude l A acenda fy pl a mil 1 PONI PWC PAC atas we ON abad Sana ra i i Vertical Offset 0 0 4 whi niej ella yng Wyk Sms 2 w 6 esa Histogram CH4 histogram count mm do 3 r10 02 I 1 1 i I i 1 1 I I a 1E 6 2E 6 3E 6 4E 6 5E 6 6E 6 7E 6 8E 6 9E 6 1E 5 Time 27 5 3 a U 0 I I I I 8E 8 8 2E 8 84E 8 8 0E 8 88E amplitude Figure 2 Front Panel in LabVIEW after Simulation 5 CONCLUSION Design of the virtual instrument achieves function of controlling oscilloscope Friendly software interface simple operation strong human computer interaction programming is easy convenient and good scalability It can be used for industrial medical cont
73. owing features of the gap Air bubbles the fewer the air bubbles the better as if these air bubbles are close to the edge it can serve as a path for charge to build up and transfer to materials nearby The label both sides have to be labeled correctly as the high voltage and ground sides respectively The cable and its connections the cables must have the wires connected to the corresponding high voltage or ground side and must not be damaged 19 The PET coating on both high voltage and ground sides the coating must be even with minimum gaps or deformations Glue excess sometimes an excess of glue is present because of the application of the PET coating This is undesirable as it impairs the flat and even surface that the PET coating is Supposed to produce Gas inlets these are very important as they serve as an access point that allows us to pressurize the gaps They are quite fragile so while moving the gap caution must be taken to insure the inlet is not damaged and remains intact The sides of the gap must also be checked for any signs of damage Leak test Once the visual inspection is completed the gaps can now be leak tested This is done by pressurizing the gap and observing it over a period of 10 minutes A computer monitors the pressure and the pressure drop after the required time is noted This helps calculate the leak rate of the gap The gaps are leak tested twice both at approximately 5 millibar and 15 millibar
74. photon into electric signal in various steps The output was observed in the oscilloscope as a plot of Voltage vs Time and histograms For every pulse received from the PMT a particle was counted to be detected by the scintillator A scintillator is a material which exhibits scintillation the property of luminescence when excited by ionizing radiation Luminescent materials when struck by an incoming particle absorb its energy and scintillate i e reemit the absorbed energy in the form of light Pic Scintillators used PMT used There are many desired properties of scintillators such as high density fast operation speed low cost radiation hardness production capability and durability of operational parameters 64 The first device which used a scintillator was built in 1903 by Sir William Crookes and used a ZnS screen The scintillations produced by the screen were visible to the naked eye if viewed by a microscope in a darkened room the device was known as a Spinthariscope The technique led to a number of important discoveries but was obviously tedious So in the TIF lab we use the PMTs instead of the naked eye observations We have arranged the scintillators parallel to each other on a cosmic stand as follows in the picture lt m l s pomy Er y FLET Each scintillator is connected with a PMT such that each of them could give an output signal in correspondence with the particle detection by t
75. plication that is written by us has the following features It configures the scope to take data one waveform each from any number of channels when there is an external trigger It saves the data to csv format in a file File name can be given at the front panel before execution of the program We can enable or disable any number of channel from the four channels of the oscilloscope We can control amplitude time scaling trigger delay and trigger position from the front panel Number of triggers to save i e number of events We can read the file even when program is running and if there is any error we can stop the execution instantly The LABVIEW program can save the waveform file in such a way that it shows the date and time of each event occurred at the moment of triggering Format of the waveform data saved is given below Event 0___ Josoneors tzasoo Channel O __ 0 859292 0 909106 0 884199 0 884199 0 01245 0 024907 Even 1 osovo rss Po Channei3 0 909106 0 909106 0 896652 0 884199 0 0 01245 0 01245 140725 1 39479 45 Now charge of the signal is calculated using mathematical functions present in LabVIEW and histogram is plotted The purpose of plotting histogram is to calculate charge of the signal coming from Photo Multiplier tube The reason behind calculating charge is that the output signal of a PMT is charge which is equal to number of photo electrons multiplied by the gain of the
76. rithm to reconstruct cosmic muon tracks using three reference chambers installed in the telescope 57 e After a successful cosmic test every chamber is powered on and monitored for about three days in order to check its stability over tme QC4 If dark current is found to be stable a pair of chambers one RE4 2 and one RE4 3 type is assembled into a super module This assembly task reduces the amount of time needed to install all RE4 detectors at CMS Since the RE4 2 and RE4 3 chambers share the same cooling circuit and gas pipes and are mechanically attached to the same structure several commissioning protocols are performed before the real detector installation at CMS MN Un ea 23 ANIA alan ACKNOWLEDGEMENT An endeavor over a period can be successful only with the support and advise of wellwishers I take this opportunity to express my gratitude to all those who encouraged me to complete this project I express my sincere thanks to Dr Archana Sharma who gave me an opportunity to be a part of a project associated with CMS collaboration CERN I am deeply indebted to my supervisor Mr Stefano Colafranceschi and Mr Brian Dorney who acted as a mariner s compass and steered me throughout the project voyage through their excellent guidance and constant inspiration I would be failing in my duty if I don t acknowledge my indebt to Mr Choi for his valuable guidance and support at each and every stage of the internship
77. rol and it is highly practical with the rapid development of computer technology and the measurement and control technology 6 REFERENCES 1 National Instruments www ni com 2 LabVIEW Application Builder User Guide National Instruments Corporation 3 National Instruments Discussion Forum 4 Lecroy Waverunner 104 Mxi User Guide 49 MEASUREMENT OF CAEN SY4527 POWER SUPPLY l ABSTRUCT In this report measurement of high voltage power supply CAEN SY4527 has been done SY4527 is a Universal High amp Low Voltage Multichannel Power Supply Systems for Detectors The System has been specifically designed to power the variety of detectors found in modern Physics Experiments such as photomultipliers wire chambers streamers tubes and silicon detectors and also to power Beam Halo Monitor INTRODUCTION The system is modular and flexible enough to be appropriate both for major experiments where a large number of channels must be remotely controlled and for test laboratories where simple manual operations on a limited number of channels are often desired The modularity of CAEN SY4527 is appreciated over CAEN SY1527 for the easy maintenance of the CPU fan unit and the power modules This will make the maintenance repair and upgrade much easier compared to the SY 1527 2527 The tests show no significant difference in performance of the boards whether operated in the SY 1527 or in the SY4527mainframe Instead of CAEN Sy1527 CAEN SY4527
78. rry me a long way in the journey of life on which am about to embark would like to thanks Mrs Archana Sharma who served as the source of inspiration and continued to help me in tough situations am grateful to Dr N K Roy and Dr P Kumbhakar who made this project possible and supported us in whatever way he could am deeply thankful to my friends Saswata Das Rahul Sinha Nancy Nayak Sandipan Das and Priya Prasad who helped me throughout my project Last but not the least thank my parents who are the ultimate source of energy and always embraced me with their countless blessings 37 CERN Summer internship 2014 Report Development of Vfat interface application for XDAQ system of CMS Experiment SUPERVISOR Dr Jared T Sturdy NAME MRINALINI INSTITUTE D T U New Delhi INTRODUCTION VFAT2 is a trigger and tracking front end ASIC designed primarily for the TOTEM experiment VFAT2 fits into the Totem electronics as shown in figure To the next element in the ring amp back to the FEC FEC control signals from previous elem in the ring The VFAT2 chip has 128 identical channels It is a synchronous chip designed for sampling sensors at the LHC clock frequency of 40MHz Each channel consists of a preamplifier and shaper followed by a comparator If a particular channel receives a signal greater than the programmable threshold of the comparator a logic 1 is produced for one clock cycle
79. s seen that the waveform stabilises after a certain amount of warm up hence giving definite values of rise time and fall time The rise time and fall time for the amplifying as well as non amplifying output give inconclusive results when monitored in the scope This might be the result of noise arising from the connectors or wires The mechanical holes that has been drilled on order to pass the wires from the output port of PASA to scope should be redesigned so that they do not touch the modified connecting wires and apply pressure on them 82 Before beginning the test every time the back plane and the PASA should be checked whether the supply voltages are okay and the output voltages from the PASA are proper Test 1 for PASA V ACKNOWLEDGEMENT I would like to take this opportunity to thank the entire ADA ADC team that I have worked with for the past 2 months as part of my CERN Thanks especially to my supervisor Jean Pierre Revol summer internship at for making me an integral part of the ADA ADC team Also thanks to Evgueni Usenko and Alexander Kurepin Huge vote of thanks to the Mexicans MArio Rodriguez Cahuantzi Ildefonso Leon Monzon Mario Ivan Hernandez for being with me while I performed the test and attending to any problems I faced during the test Thanks also to Luis and Abraham for cooperating and providing necessary help whenever reguired Also thanks to Ernesto Calvo and Martin Poghosyan for
80. s such that no light falls on the surface Now it is connected to the setup as described above and the PMTs are powered High voltage of 1500V was applied to the photo cathode of the PMT and the oscilloscope trigger was set to 50mV to cut off the noise Now we were using a light source on the surface of the scintillator and checked for any unusual rise in the counter value If there is an unusual rise this implies that there is leakage and that area needs to be insulated better And as the requirement of the procedure all the scintillators were properly insulated e TEST No 2 The PMTs were directly connected to the oscilloscope to verify that the pulse voltage from these PMTs are always kept below a required level such that it is lower than the voltage level at the input of the Constant Fraction Discriminator High voltage of 1500V was applied to the photo cathode of the PMT and the oscilloscope trigger was set to 50mV Photon counter trigger was set to 50mV too The output at each stage was observed in the oscilloscope Le Croy Wave Runner as a plot of Voltage vs Time and the histogram using the measurement table tools which calculated the peak voltage of the waveform It was verified that the pulse voltage levels are kept to the required range QUAD COINCIDENCE LOGIC Scintillator BOARD PULSE COUNTER Scintillator PMT setup with oscilloscope 67 EFFICIENCY AND ERROR TEST In a cosmic stand the scintillators are arrange
81. software instrument concept User self definition and design and the corresponding function can be designed according to the demand And it can reach one or even multiple functions of traditional instruments in an integrated environment and easy upgrade and expansion cost effective Now we have constructed a versatile virtual digital acquisition in the construction demand from the laboratory for measurement and control which has been applied and received distinct effect The Virtual Instrument Software Architecture VISA is a standard for configuring 44 programming and troubleshooting instrumentation systems comprising GPIB VXI PXI Serial Ethernet and or USB interfaces VISA provides the programming interface between the hardware and development environments such as LabVIEW LabWindows CVI and Measurement Studio for Microsoft Visual Studio NI VISA is the National Instruments implementation of the VISA I O standard NI VISA includes software libraries interactive utilities such as NI I O Trace and the VISA Interactive Control and configuration programs through Measurement amp Automation Explorer for all our development needs 3 SCOPE OF WORK We will have a setup for measurements using cosmic rays A device will produce a trigger signal an LVTTL pulse on a standard lemo cable that will be connected to the dedicated trigger input of the scope This device is controlled by another LabVIEW program The features of the LabVIEW ap
82. sponsible for sending On Detector Off Detector signals via the optical links to the NIEZ he front end electronics Gigabit Link Interface Boards are housed in a GEM Electronic Board UTCA crate e GLIBs communicate with the Opto Hybrid eee micro TCA chamber electronics via optical fibers Tiger LinkstoCSCs AMC13 pag and sends data to the central DAQ Optical Inks 3 2698 DCS TTC e A uTCA Controller Hub connects to a PC and provides control of the GLIB through software over UDP via a jabang protocol called IPBus developed by CMS TTC Clock L1A Fast controls CMS DAQ Link optical Versatile Link Front End Electronics Micro TCA crate GbE for configuration Poa R Slow controls SEEN Ce Se See ee ee aa Figure 2 GLIB and MCH GLIB System Registers and their address Addr Name Description Type 0x00 Board_ID The board identifier code RO 0x01 System_ID The system identifier code RO 0x02 Firmware_ID The firmware date and version number RO 0x03 Test_Reg Register for test purpose only RW 0x04 Ctrl Control the external clocking circuitry RW 0x05 Ctrl2 Flash control RW 0x06 Status Status from various external components RO 0x07 Status2 Currently not used RO 0x08 Ctrl SRAM SRAM interface Control RW 0x09 Status SRAM SRAM interface Status RO OxOA SPI_txdata SPI interface data from
83. t hindered location MOISTURE plays an important role too Water may enter the adhesive either by diffusion or by capillary action through cracks and crazes and alter the properties of adhesive UV Radiation can also enhance ageing by breakdown of the material leading to discolouring loss of toughness and embrittlement Consideration must be given to the Behaviour of joints constructed with adhesives as joint behaviour is largely determined by joint s geometrical configuration in which it is MECHANICALLY loaded Conclusion Well seeing all the reasons Reason No 5 Ageing of the Glue seems more powerful and a possible reason for the leakage to happen in the C6F14 radiator On the other hand failure to happen by other 4 ways seems very bleak at present There is even a great amount of limitation for the minimization of this problem as the access to the detectors can only happen once the entire run of the detector is complete Search for materials of reducing the leakage is being carried out 76 Comprehensive Testing and Calibration of PASA Circuit in the ADA ADC Detector of ALICE Saswata Das Department of Electronics and Communication Engineering National Institute of Technology Durgapur Abstract The main reason for the integration of the ADA ADC detector in the ALICE Experiment is because ALICE wishes to extend its diffraction program for both single and double diffraction by improving detector efficiency detection of gaps in the pse
84. th in the range of GPa But the chances of being worn down by any deformation of Neoceram or Quartz plate if occurs may result in undue stress of tray with consequent development of cracks in plate 2 Thermal Cycles Under fluctuating cyclic stress failure can occur at loads considerably lower than tensile or yield strengths of the material under a static load The detectors were not run continuously for 4 years and a fair enough thermal change technical stops carried out during RUN 1 will very slowly start initiation of cracks in the region of stress concentration which slowly would increment if no sudden changes are allowed or drastically increment if sudden change of temperature is dropped to 9 C during the failure of cooling system This over a period of time will propagate the cracks and may be a cause of leakage 3 Hydrostatic Load Out of plane loading such as hydrostatic force creates a flexural forces for panels Classical beam theory would tell us that the loaded face is in compression the other face is in tension and the core will experience some shear stress distribution profile Bending failure modes to consider include core shear failure core to skin debonding and skin failures To withstand hydrostatic pressure 24 cylindrical spacers are glued to bottom plate on one side and quartz on the other side But chances of failure by this mode seems bleak as the radiator tray has been designed with safety factor 7 to resist the
85. to the central DAQ A uTCA Controller Hub connects to a PC and provides control of the GLIB through software over UDP via a protocol called IPBus developed by CMS aad Pn lan On Detector Off Detector alll Ml Mi VFAT3 front end ASIC m GEB GEM Electronic Board Opto Hyond Prem 7 macIcA Trigger DAL l Links io CSCs 0 om Optical links 3 2Gbps DCS TIG Power Supplies LV MV 40 VFAT REGISTERS PRINCIPAL Reg Name Hardwired Software Default Reg Cont Reg 0 Cont Reg 1 IPreampln IPreampFeed PreampOut Shaper IShaperFeed IComp ChipID 0 ChipID1 UpsetReg HitCount0 HitCount1 HitCount2 ExtRegPointer ExtRegData Sleep value 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 VFAT REGISTERS EXTENDED Value 0000 0000 0000 0000 1010 1000 0101 0000 1001 0110 1001 0110 0110 0100 0111 1000 0000 0000 0000 0000 addressed via Principal registers 14 and 15 41 type Lat 1000 0000 1000 0000 x0 W R ChanReg 1 128 0000 0000 0000 0000 xl to 128 W R VCal 0000 0000 0110 0100 129 W R VThreshold1 0000 0000 0000 0000 130 W R VThreshold2 0000 0000 0001 1010 131 W R CalPhase 0000 0000 0000 0000 132 W R Cont Reg 2 0000 0000 0000 0000 133 W R Cont Reg 3 0000 0000 0000 0000 134 W R Spare 135 0000 0000 x135 W R XDAQ FRAMEWORK XDAQ is a framework designed sp
86. udo rapidity distribution of particles during collision to study central diffraction Additional advantages like improving sensitivity to diffractive masses providing level zero trigger capabilities by counters and extended centrality trigger in both pbPb and ppb collisions PASA Pre Amplifier Shaper Circuit form an integral part of the front end electronics setup for the ADA ADC Experiment It is mainly associated with removing the time lag between two apparently similar events triggered during separate instances It requires rigorous testing and calibration to ensure both the output channels are functioning properly The paper outlines the utility procedure and the results of the various tests carries out on the PASA PASA ADA ADC Important words calibration testing I INTRODUCTION 1 ALICE ALICE abbreviation for A Large Ion Collider Experiment is an experiment at the Large Hadron Collider LHC optimized for the study of heavy ion collisions at center of mass energy almost equal to 5 5 TeV The prime aim of the experiment is to study in detail the behavior of matter at high densities and temperatures in view of _ probing deconfinement and chiral symmetry restoration The goals of ALICE involving particle identification are the measurement of global event characteristics like event topology momentum spectra of identified particles particle correlations HBT and particle ratios the measurement of the phi dec
87. ur LCD 10 4 touch screen optional REMOTE RS232 TCP IP Gb Ethernet Wi Fi optional CONTROL CAEN SY4527 Figure 3High Voltage Power Supply CAEN SY4527 SOME ADVANCED FEATURES OF SY4527 e Communication via Gigabit Ethernet Wi Fi optional e OPC server too is Integration in DCS e Fast accurate setting and monitoring of channel parameter e Live insertion of boards e Advanced trip handling e Hardware current protection 51 e Secure access to the system via Intranet e Application Software for remote control e Graphical wave interface e Easy firmware upgrading 3 EXPERIMENT STEPS THAT HAS BEEN TAKEN FOR MEASURING SY4527 Download GECO Software 2020 to communicate with Mainframe and the power supply Make a resistor box of 12 resistors you can make with 24 resistors too each of resistance 1 mega ohm SPECIFICATION OF POWER SUPPLY CAEN A1535SN Maximum Voltage 3 5kV Maximum Current 3uA BASIC CPU We set VOset to 2 8kV and IOset trip current 3 uA Now we can measure V mon and Imon Imon will reach up to 2 8kV Imega ohm 2 8 mA So here no trip occurs First 12 channels are checked for 48 hours and then next 12 channels are checked GECO is connected with power supply using IP address 137 138 168 21 and user name and password as admin Pw on Ramp up 50 Vps Ram down 50 Vps Trip 10s and we can get Vmon and Imon Each testis run for 30 to 48 hours During the burn in test we have to be able to chec
88. usly it can fulfil our need In M76 skins that which has thickness 1 05 mm is preferred for its good Mechanical and thermal properties 1 2 Analysis of Ring with support plates in ANSYS 15 Now the analysis is done with support plates with modules again changing the different carbon fibre skins while keeping the material of foam core same Further von mises stress total deformation directional deformation in X Y and Z direction are recorded 11 Above is the analysis result from ANSYS Workbench 15 when in plane acceleration due to gravity is provided as loading plus the density of the support plate is increased to compensate the weight of Module which are here considered as of 35g This ring structure is provided three fixed point and support plates and carbon skins are modelled as shell In this analysis result skin of K13D2U is used which shows the maximum deformation of 11 7 um g Above is the analysis result of Ring with K13D2U as skin material but loading is provided as acceleration due to gravity out of plane In this analysis the maximum deformation possible is 21 mm Observations The possible maximum total deformation when acceleration due to gravity is in plane is 11 7 micrometre which is on support plate Deformation on the support plate should be as low as possible so that modules can be placed at predefined orientation and the maximum possible total deformation when acceleration due to gravit
89. ver the RPC e About 5 kg of weight is applied over the position of each spacer If the spot does not show any significant fluctuation in pressure it means that the spacer is 56 3 HIGH VOLTAGE TEST In the electric test the front end boards are powered and checked while the gaps are subjected to an high voltage scan to ensure that the RPC gaps operate without problems Finally the core of the QC3 protocol is the chamber by chamber performed high voltage scan that aims at characterizing detector response while measuring main detector performance parameters such as efficiency cluster size and noise Since the RE4 chambers are based on double gap RPCs each detector is subjected to three independent efficiency scans using three different configuration double gap top single gap bottom single gap During one efficiency scan 7 runs at different effective HV are taken from 8 5 to 10 kV m each run 10k events are collected m approximately 2 hours KODEL CMS RE4 3 TN100 sya TN100 5 un LEAKAGE CURRENT LEAKAGE CURRENT 0 2000 4000 6000 8000 10000 12000 200 300 400 500 600 700 800 APPLIED HIGH VOLTAGE TIME Measured values of a sample RPC RE4 3 TN100 4 COSMIC STAND TEST e Each cosmic telescope 1s equipped with two scintillator layers top and bottom that form the trigger e The chamber front end boards are connected via flat cables to TDCs to tag and record all hits e The analysis routine performs a tracking algo
90. was at my side whenever at whichever hour of the day needed him He would always support me with his appreciating words and grew manifold in confidence and knowledge sincerely feel my work would not have been possible without the co ordination of my fellow summer students at the laboratory Even though most of them are foreign students we got together very easily and made friends Finally also thank Mr Mohsin Abbas who was very helpful in my early days at CERN TIF Lab He explained to me many things and provided with the required equipment and materials as and when required hope this experience at CERN will help me to contribute to this wonderful world with utmost sincerity and honesty also hope to work with the people met at CERN in the near future 70 QUALITY ASSURANCE MACRO FOR ALICE S HMPID DETECTOR SANDIPAN DAS Supervisor Giacomo Volpe NIT DURGAPUR 4TH YEAR Metallurgical and Materials Engineering Department Abstract ALICE A Large Ion Collider Experiment is an experiment at the LHC Large Hadron Collider optimized for the study of heavy ion collisions at a centre of mass energy 5 5 TeV for nuclear pair The prime aim of the experiment is to study in detail the behaviour of matter at high densities and temperature in view of probing deconfinement and chiral symmetry restoration The goals of ALICE involving particle identification are the measurement of global event characteristics like event topol
91. will be used to supply power to BHM in future BEAM HALO MONITOR A fast and directional monitoring system for the CMS experiment is designed to provide an online bunch by bunch measurement of beam background induced by beam halo interactions separately for each beam The background detection is based on Cherenkov radiation produced in synthetic fused silica read out by a fast UV sensitive photomultiplier tube Twenty detector units per end will be azimuthally distributed around the rotating shielding of CMS covering 408 cm2 at 20 6m from the interaction point at a radius of 180 cm The directional and fast response of the system allows the discrimination of the background particles from the dominant flux in the cavern induced by pp collision debris produced within the 25 ns bunch spacing A robust multi layered shielding will enclose each detector unit to protect the photomultiplier tube from the magnetic field and to eliminate the occupancy from low energy particles The design of the front end units is validated by experimental results An overview of the new system to be integrated in CMS during the current shutdown of LHC will be presented and its perspective for monitoring in High Luminosity LHC 50 WHY SY4527 IS BETTER THAN SY 1527 MAX OUTPUT 2250 4200 220 Vac POWER 1990 110 Vac POWER 100 230 Vac 100 240 Vac REQUIREMENT 50 60 Hz 50 60 Hz 3400Watt 5500Watt 220 Vac 2150Watt 110Vac LOCAL CONTROL Keypad 7 7 colo
92. wires Front end electronics This converts the information coming in as electric charge into digital signal to be sent to the computer for data processing TESTING During the visual inspection each chamber undergoes a detailed checklist to validate the manufacturing process of the chamber 1 LEAK TEST Leak test was carried out two times during the development of construction One at the very beginning to see whether there is any leakage in the bakelite chamber Next one after the completion of assembly including the fixing of Aluminium wafers The process of leak test follows A suitable gas is passed into the gap through the input pipes from a source at a suitable pressure 15 mbar The output wire is connected to a manometer 55 e Once the gas is filled inside the chamber just like filling air m a balloon the further inflow of gas 1s prevented using a stopper Now the pressure inside the chamber 1s measured using the manometer and noted down e This set up is maintained for 10 minutes and the variation in pressure is noted If there is no significant decrease in pressure the chamber is not leaking else the its defective tite 2 SPACER TEST To ensure that the gap between the two bakelite sheets are exactly 2 mm The steps are as follows e The pressure variations slight though inside the chamber is read graphically using a computer e Dummy sheets of exact dimensions showing are placed o
93. with CH4 are prevented from entering the MWPC sensitive volume by a positive polarization of the collection electrode close to the radiator Each of the seven RICH module consists of a six independent photo detectors and six high voltage sectors Here we have developed a macro for quality assurance of HMPID to measure various parameters using the data collected by ALICE during RUN I Period Plots shown below have been made to compare the parameters of the detector for LHC 2010 2011 2012 SLNo Parameter Figure l X Residuals I left I right Ideft Ii right deft Ii right L IV 71 NYRasPOS 6 nYResPOS 5 Y RESIDUALS X RESIDUALS Te amy m XResiduals Xqpz Xyrp Where Xrpk extrapolated point to HMPID charge and X p closest cluster corresponding to mipCharge And same for Y Residuals Gaussian Fit is symmetric with respect to x 0 for X residuals but not for Y Residuals due to residual misalignment not perfect TPC calibration and underestimate of the material budget in front to the HMPID FIGURE I o l ggg g yn 8 8 S a mipCharge charge produced in MWPC along the track Occupancy no of charged pads over the where the plot is a Landau distribution total charge FIGURE II N Pions 5 25 Kayons 2 Protons 20 15 10 5 005 01 O15 02 0 25 03 035 04 Sin exe Plot of Cherenkov Angle vs Momentum No of Photons No of detected Cherenkov
94. y is out of plane is 0 19 mm 1 3 Analysis of Thermal Behaviour of Ring Structure The support structure of CMS Tracker BPS is exposed to very adverse condition especially the temperature ranging from 50 to 50 C so coefficient of thermal expansion creates some extra deformation and fatigue to the support structure along with loading and self weight Modelling is done same as earlier only thermal condition is included additionally In thermal condition full body is kept at uniform temperature For all three carbon skin the deformation due to self weight and temperature variation is noted and plotted Observation Temperature Vs Maximum Deformation 0 0008 K13D2U Cyanate Ester M55 m E E amp Temperature Celsius The above plotted graphs are of total deformation Vs temperature when the in plane loading acceleration due to gravity is provided Since the coefficient of Thermal Expansion is negative for all the carbon fibre skin so on increasing the temperature below environment temperature deformation goes down but as it crosses the environment temperature the total deformation increases in linear manner For carbon Fibre skin K13D2U an in plane acceleration due to gravity causes the maximum total deformation of 00046 m while for skin M55 same type of loading gives the maximum deformation of 0045 m and for skin T800 the maximum deformation possible is 0078 m Temperature Vs Eguivalent Stress 6 00

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