LTU Site Report

1. LTU Site Report Dick Greenwood Louisiana Tech University SW-USA TRACKER WORKSHOP University of Oklahoma January 15, 2007

2. RunIIB Silicon Efforts at DØ With Andre Nomerotski, Marcel Demarteau, Ron Lipton Students: Moreshwar Dhole Sowmya Kandula Kasi Godivarthi

3. RunIIB Readout One hybrid is an independent unit Separate cable up to an accessible region Same as in Run2A, proven to be successful during Run IIA commissioning Minimizes readout time Simpler testing and stave construction Jumper Cable - Junction Card - Twisted Pair Cable – Adapter Card New Adapter Card is active, implements necessary modifications Junction Cards are located in an accessible area Twisted Pair Cable is well suited for differential SVX4 readout

4. Digital Jumper Cable Hybrid - Jumper Cable - Junction Card - Twisted Pair Cable – Adapter Card • Designed by Kansas State • Same design for all layers • 10-12 different lengths, max length ~ 1 m • Kapton substrate, total thickness 250 um for L0-1, 330 um for L2-5 • HV on the same cable • AVX 50-pin connector on both sides • Layout reviewed and prototypes ordered in January 2002 • From Honeywell (Run2A low mass cables) • Back in March 2002 • Electrical, mechanical tests OK • Second vendor : Basic Electronics • Received 10 cables, tested OK

5. A Closer Look At the Digital Jumper Cables • Low-Mass Flex-Circuit Striplines • 11 Differential Signal Pairs • 6 Single-Ended Signals • 5 Sense Lines • 2 Supply Voltages and Ground Returns • Initial Task: Test Prototype 50 cm Digital Jumper Cables • Measure resistance • Check for cross-talk • Measure impedance

6. Digital Jumper Cable Readout Setup

7. New Board Design (Tom Emory, ZDG)– Made at Fermilab

8. Sowmya Kandula’s Work • Burn-in tests and the functionality tests of Layer 0 hybrids • crucial in ensuring the desired operation of the readout chain • Employed the new custom made SVX4 chips which were also tested •  found to be very reliable and well-suited to the needs of the DØ experiment

9. Kasi Godavarthi’s Work • Laser Testing to Determine the Charge Distribution in Adjacent Channels of Silicon Detectors at FermiLab

10. LaserTesting • Final characterization of silicon detectors made by using the laser • test system. • The laser was pulsed externally using a pulse generator. • EG&G 1064nm laser was used. • Light was transmitted via an 6.2um optical fiber. • Principle of operation. • Pulse height measurements are used to identify dead channels and also to determine various electrical characteristics of the detectors such as depletion voltage and leakage currents. • The total number of dead and noisy channels had to be less than 5% of the total channels in the detector. • The detector is placed on a table which can move both in horizontal and vertical directions. • The lens system is fixed to a system which can move in the vertical axis with a micrometer is attached.

11. High Voltage Patch Panel - 4 Karthik Reddy Louisiana Tech. University

13. Introduction • HV and LV deliver power to • half staves • disk sectors related to PP4 which connect to each detector module individually • PP4 crates provide • current monitoring for single individual modules.

14. High Voltage System • The simplest one • A unique requirement of the HV distribution system is that the modularity, the number of detector modules supplied in parallel with same supply channel, be configurable from 6/7 modules per HV supply channel to 2 modules per channel.

15. High Voltage System • HV supplies are present in • US15 and USA15 • Connect 6/7 modules to a single High voltage supply channel via HVPP4. • HVPP4 also provides individual current measurements via ELMB. • Uses I-Seg 16 channel system to drive the PP0 systems.

16. Patch Panel 4 • One of the series patch panels or connectivity points • Distribute the services to pixel detector. • Physically located • US15 and • USA15.

17. Need for Current Monitoring • To isolate the detector. • Because we connect 6/7 modules for each High Voltage Line. It is necessary to monitor the current in each module and also to know how much current is being drawn by a single module. • Also to monitor the current in each module after they are exposed to the radiation.

18. Electrical Requirements • Measurement Accuracy should be at least 5%. • Measurement range should be 0.4uA-4mA. • Measurements circuits must be interface to the ELMB ADC inputs. • Circuit design should withstand 700vDC. • Life of the circuit HVPP4

19. Simulation Software(PSpice) • PSpice • Components • LM359-Norton dual current input amplifier. • HCNR 200- opto-isolator • Resistors and capacitors

21. Protection of detector • Design steps to protect the detector • Current tappedacross the resistance is given as input for the two pins of LM359. • The output of this amplifier is given as input to the other amplifier acting as voltage amplifier. • The sole purpose of this amplifier is to give the supply voltage to the optoisolator(HCNR200). • The light emitted by the LED in the opto-isolator is absorbed by the phototransistors.

22. Protection of detector • Steps continued.. • Opto-isolator has two outputs, one is given as feedback to the second stage amplifier • Other output is input to a buffer • Output of the buffers is then fed to ELMBs • Current sensed is transmitted to DCS via CAN

23. Future HVPP4 • Finalize present design • Analog amplifiers can be replaced by magnetic amplifiers

24. ILC R&D Program at Louisiana Tech University Lee Sawyer SW-USA Tracker Workshop Norman, OK 15 Jan 2007

25. Detectors for the ILC • Currently there are “four” detector conceptual design collaborations • SiD: All silicon detector (Si tracking, W/Si calorimeters, …) Heavily U.S. • LDC: TPC as central tracker, with Si inner tracking, and W/Si EMCAL. Heavily European. • GLD: LDC with a Japanese accent. • 4th: Hauptman/Wigmans DREAM calorimeter with a detector concept (TPC, dual solenoids) wrapped around it. • In addition there are several international R&D collaborations (CALICE, LC-TPC, SILC)

26. Motivation for Forward Instrumentation • Luminosity Measurements • Measure differential Bhabha cross-section • May require greater angular coverage than trad. LUMCAL • Need > 0.1% luminosity determination at high energy • GigaZ running requires very precise (10-4) luminosity + beam energy determination • Other luminosity ideas? (WW, Z’s, …) • Hermiticity and Granularity • Important physics signatures require tracking up to cos(q) ≈ 0.99 • e+e- -> WW, other t-channel Standard Model processes. • Selectron searches • SUSY searches with small slepton-neutralino small mass differences • Tag electrons from gg • Tag low pT tracks • Additional Concerns for Very Forward Region • High Backgrounds • Monitoring Ebeam, Polarization

27. What Are the “Benchmarks” for Forward Instrumentation? • For luminosity measurement, polar angle resolution dq for forward elements as important as as dp/p • This should complemented by sufficient high energy resolution and electron ID in forward section of ECAL and LUMCAL • Energy Flow benchmark requires hermiticity and granularity • Final layout of far forward elements (LUMCAL, Bhabha counter, …) depends on machine interface. • How well can these different elements be incorporated into an energy flow algorithm?

28. The Large Detector Concept (LDC) • TPC • 5-lyr Pixel VTX det. • Si strip inner det. • Forward pixel & Si strip tracker • W/Si EM Cal • Fe-Scintillator or Fe-RPC HAD Cal. • 4 T solenoid w/ return yoke

29. ILC R&D at LA Tech • Primarily concentrating on the Endcap Tracking Detector (ETD) in LDC • Called FCH in the TELSA TDR • Forward Tracking Studies • Developing LDC geometry file for SLIC • Studying resolution requirements in the intermediate to forward angles. • Studying effect of the TPC endplate on tracking resolution at intermediate angles • Detector R&D • GEM chamber development with large foils • Compact GEM tracking chambers (thin material profile) • Collaboration between HEP and Nuclear groups at LA Tech (QWEAK experiment)

30. LA Tech on LDC • Took part in drafting current Detector Outline Document (DoD) • Co-Editor of Supplementary Tracking chapter • Includes some simulations results obtained at LA Tech • Simulation Wars: Two ways of generating detector simulations • SLAC: STDHEP input => SLIC GEANT interface => org.lcsim reconstruction • DESY: STDHEP input => MOKKA GEANT interface => MARLIN reconstruction • We have worked on geometry in both MOKKA and SLIC frameworks • Both branches use LCIO file format for output • E.g. Should be able to reconstruct SLIC output with MARLIN • We are testing this at LA Tech. • Detector R&D collaboration • Recently joined the LC-TPC collaboration • Common interest in gaseous detectors (GEMs, micro-megas) • Development of ETD cannot be independent of TPC endplate design

31. ETD Development GEM Prototypes SLIC vs MOKKA

32. Recent LCRD Proposal • Joint proposal with • Oklahoma (Strauss), • Indiana (van Kooten) and • LA Tech (Sawyer, Greenwood, Wobisch; Wells) • First step in a possible Forward Tracking R&D collaboration a la CALICE or LC-TPC. • Continuation of previously described work at LA Tech • Assistance from OK and IU in test beam, electronics development • Year 3 of 3-year renewal cycle. • Strong new effort from OK in forward tracking algorithms. • Collaboration in detailed forward studies, incl. low angle forward tracking (i.e. FTD).

33. The End

34. Extra Slides

35. A HV-PP4 is therefore not only capable of a current measurement of the HV-lines on a single module level (by the use of ELMBs), but it is also responsible for the correct mapping of the iseg HV channels to the detector modules. 16 HV-PP4 crates will be required for the experiment, each with up to 117 monitoring channels.

36. Current Monitoring • The circuitry included in the HVPP4 design contributes to this protection system by sensing the current flowing through High voltage cables and making the reading available through ELMB to the DCS.