LHCb RICH HPD Photodetector Test Facilities

1
LHCb RICH HPDPhotodetector Test Facilities

• Aims and Strategy
• Test Program
• Infrastructure / DAQ System
• Photo Gallery
• Software
• Issues for Discussion

Stephan Eisenhardt University of Edinburgh
meeting with DEP, Roden, 18.03.2004
2
Aims and Strategy

• Verify specs of 550 HPD tubes and characterise
  them for selection over 18 months
• delivery from DEP to Edinburgh Glasgow
• rate of 30 HPD per month
• max. 8 weeks from delivery to provisional
  acceptance of HPDs
• Photo Detector Test Facilities (PDTF)
• two PDTF sites Universities of Edinburgh
  Glasgow
• two test stations per site (i.e. 4 DAQ chains in
  total)
• one test station/site for mandatory tests for
  provisional acceptance
• second test station/site for extra
  characterisation and redundancy
• test one HPD / work day / site
• automation is essential

3
PDTF Team

• PDTF Project Leader / Quality Assurance Manager
• Franz Muheim
• Site Manager University of Edinburgh
• Stephan Eisenhardt
• Site Manager University of Glasgow
• Andrew Pickford
• Test programme will be shared between
• 3-4 people/site
• physicists technicians

4
Test Program

• Mandatory tests (one test station / site)
• mechanics (sizes and tolerances)
• pixel chip register check DAC linearity scan
• threshold working point, scans, TP noise
  threshold maps
• DAQ timing
• LED test dead pixel map, sensor position,
  demagnification
• HV scan gain curve
• Bias V scan depletion IV-curve
• dark count rate ion feed back rate

5
Test Program II

• on 2nd test stations
• Extra characterisation (on subset of HPDs)
• photoelectron efficiency with backpulse
  measurement
• quantum efficiency measurement with Sr90 source
• electron optics distortion map
• Additional studies (on subset of HPDs)
• swap tubes between sites and re-test for
  cross-check
• re-measure for long-term stability
• Redundancy
• immediate spare if first test station fails

6
Infrastructure / DAQ System

• based on CERN HPD DAQ
• similar to system at DEP
• hardware status
• 4 full DAQ chains
• 2 spares for custom electronics
• usable for prototype and
• production HPDs
• 1 setup operational
• operated HPDs at Edinburgh
• _at_ 20kV 80V bias
• plan to have 4 setups in April
• HPD storage
• in DEP boxes plastic bags
• under N2 atmosphere

• improved automation
• no more hand-steered/recorded
• parameters
• Silicon Bias Voltage steering
• Silicon Bias current read back
• LED delay setting wrt. DAQ clock
• Temperature monitors

7
Photo Gallery I
bias pick-up
dark box
HPD
pA meter
flat pointing light source
DAQ PC
bias supply
electronics supplies
MB/FB supply
LED trigger
PP JTAG
fibre
to ZIF board
LED pulse
MB FB
PCI bus
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Photo Gallery II
HV interlock
light sources
HV supply
HV distribution
HPD
I/O board
independent PMT
HV interlock
sealed divider chain
LED
HV terminal
fibre mount
prototype HPD
9
Software
LED delay control

• DAQ based on Labview und WinXP
• custom software PTS (DAQ), monitoring, task
  flow,
• commercial software Labview, hardware drivers
• analysis code based on UNIX/HEP tools
• PDTF software status
• PTS software working
• Labview-HW interfaces monitors working
• automation of test tasks work in progress

PDTF task flow control
HV control
BiasV control
T sensors
10
Conclusions

• setup of photodetector test facilities at
  Edinburgh and Glasgow is well underway
• 1 DAQ setup is operational successful HPD
  operation
• 4 operational DAQ chains in April 05
• stand-alone software for all components working
• further software integration for automated test
  programme underway, to be finished in May 05

11
Issues for Discussion

• in agreement with contract technical
  specifications
• Schedule
• details of revised delivery schedule of summer
  05
• plans for Christmas 05 / summer 06
• proposal for delivery scheme
• 2 sub-batches/month interleaved between
  Edinburgh/Glasgow
• maximum production rate at DEP
• Packaging
• N2 atmosphere for HPD when shipped from DEP
• Info on HPD supplied by DEP
• prefer fixed file format, e.g. template of Excel
  spread sheet
• Lines of communication
• generally via QA manager
• next visit after production of first (few)
  batch(es)

setup of photodetector test facilities at
Edinburgh and Glasgow is well underway 1 DAQ
setup is operational successful HPD operation 4
operational DAQ chain