WBS 2'5 HF PMT SYSTEM

1
WBS 2.5 HF PMT SYSTEM

• Y. Onel
• University of Iowa
• US CMS DOE/NSF Review
• May8-10, 2001

2
Outline

• HF PMT Specifications
• Previous Experimental Data on Photodetectors by
  HF Group
• Tasks of the Test System
• Procedures for measurements
• Quality Assurance
• HF PMT Test Station
• Preliminary HF-PMT Candidate Tests/Specs
• Experimental Data
• Manpower and expert team to install the test
  system
• Vendors
• Milestones
• Conclusions

3
Previous Experimental Data on Photodetectors by
HF Group
R6427
4
HF Radiation Environment

• Recent radiation background simulations show
  improvement in the design of the shielding around
  the PMT region by a factor of two. There is no
  issue with the radiation dose or neutron flux
  where the PMTs are located.
• All neturons 2.54x1012
• Neutrons (Egt100KeV) 1.63x1012
• Neutrons (Egt20 MeV) 5.12x1011
• Ch. Hadrons 2.26x1010
• Muons 4.65x109
• Photons 1.53x1012
• Dose 7 krad

5
HF PMT Quantum Eff.

• ltQEgt gt15 400-500 nm

QP Fiber 54 Mrad Dose
6
HF-PMT Specifications Summary

• Window Material Borosilicate glass
• Effective photocathode dia 22 - 28 mm, head-on
• ltQEgt gt15 400-500 nm
• Photocathode lifetime gt 200 mC
• Anode current vs position lt /- 20 with 3 mm
  spot scan
• Gain 104 to 105, 105 at lt 0.75 x VKA(max)
• Single pe resolution rms/mean of single pe peak
  50 or better
• Pulse linearity /- 2 for 1-3000
  photoelectrons
• Anode pulse rise-time lt 5 ns
• Transit time lt 25 ns preferred
• Transit time spread lt 2 ns preferred
• Pulse width lt 15 ns FWHM
• Gain (1/2)-lifetime gt 1500 C
• Average current IK lt 1 nA ( g 104 )
• Average current IA lt 10 mA ( g 104 )
• Anode dark current lt 2 nA ( g 104 )
• Stability lt /- 3 within any 48 hr. period
• Envelope opaque and HV conductive coating

7
Tasks of the PMT Test System

• HF PMT Quality Control and Test System will
  address the following items
• label and catalogue each PMT at delivery and
  storage
• mechanical assembly with HV power supply and
  base
•  installation in Test Boxes individually or in
  groups

8
Procedures for measurements

• The following sequence of measurements will be
  performed for each PMT or each PMT batch
• 1 - PMT's installed in Test-Box are let to
  stabilize at standard HV each tube
• 2 - Check of normal operating conditions each
  tube
• 3 - Noise and dark current measurements vs.
  HV each tube
• 4 - Gain vs. HV laser each tube
• 5 - Single photoelectron level each tube
• 6 - Linearity for 1- 3000 p.e. each tube
• 7 - Rate dependence for 0.1 - 40 MHz LED
  each tube
• 8 - Photocathode uniformity for each batch
• 9 - Quantum efficiency (300-600 nm) dye
  laser for each batch
• 10 - Pulse shape measurements at nominal HV.
  for each batch
• According to specifications of the PMT
  (manufacturer's data sheet and preliminary
  measurements on a test sample) and requirements
  of HF application (Nphe/GeV, dynamic range, etc.)
  the test setup working conditions will be
  adjusted in a range of light yield and
  sensitivity appropriate for the standard test
  procedure. Three light sources will be used for
  the specific measurements
• - laser
• - LED
• - Rad. sources radiator

9

• Measurements will be performed at stable
  (controlled) temperature using defined procedures
  for each PMT or each PMT batch.
• Light sources will be installed (Tungsten Lamp,
  Laser, Dye Laser, Laser Diodes) for the specific
  measurements
• The data for each PMT will be stored in
  appropriate archive files on disk and copied to
  permanent storage media. For each PMT an entry
  will be printed and logged to a general PMT
  directory and test logbooks.
• The PMT's conforming to acceptance criteria,
  will be sorted in classes and stored. Those not
  conforming will be returned to the manufacturer.
• All measurement procedures will be automated and
  computer-controlled, to minimize individual
  biases and interventions daily test shifts will
  be supervised by an expert, who will also review
  the archived data of the day and certify their
  validity.
• The fully automated PMT Test station will contain
  (x-y scanners, neutral density filter wheels
  computer controlled, optical bench, DAQ
  LabView and interface systems.)

10
Quality Assurance

• At the manufacturer
• testing/preselection as they arrive
• beam/calibration tests during the installation
  period
• PMT can be replaced

11
HF PMT Test Station
IEEE 488
Calib Power Meter
sync trig
Scope
VARIABLE ND FILTER
ND Filter
D8
LASER DIODE
0-3mm 635 nm
CW base
PMT
Nano-ammeter
A
PC
sync trig
x-y stage
CAMAC ADC
GATE
PULSAR
gate
W/ double 41 option
scsi
12
PMT Measurements

• 1. Quantum Efficency
• 2. Dark Current
• 3. Gain
• 4. pulse height resolution
• Gain vs. High Voltage
• Linearity and pulse-rate dependance
• Rise-time
• Transit-time
• Transit time spread
• Pulse width
• Current vs. Photocathode spot position
• Anode sensitivity vs wave length
• Vendor measurements
• Iowa measurements on the candidate tubes

13
Manpower and expert team to install the test
system

• UI
• U. Akgun (DAQ, Pulse Setup)
• A. Ayan (DAQ, Pulse Setup)
• P. Bruecken (Dye Laser System, Pulse Setup)
• M. Miller (LED System, Optical Installation,
  Electronics)
• Y. Onel (Project Manager, Procurement, Specs)
• I. Schmidt (Mechanical Installations,
  Electronics, Gain Setup)
• Post-doc (TBN) (Test Facility Manager)

• ISU
• W. Anderson (DAQ, Specs)
• Fairfield U
• D. Winn (Gain Setup, Specs)
• International Team
• I. Dumanoglu Turkey (DAQ)
• E. Gulmez Turkey (Electronics, Trigger)

14
Preliminary HF-PMT Candidate Tests/Specs

• Measurements
• Anode Dark Current
• Leading Edge Rise Time
• Pulse Width
• Transit Time
• Transit Time Spread
• Current Gain
• Linearity

15
Photodetector Linearity Measurements
16
Neutral Density Filter Setup
17
Scope View
18
Transit Time, Rise Time, Pulse Width
19
Gain Dark Current
Gain
Dark Current
20
PMT Manufactures Contacted and Candidates

• Hammamatsu R7525
• Electron Tube D843WSB D844WSB
• Photonis XP2960 XP3182
• Burle no response
• ADIT no response
• Melz no response

21
Procurement/Testing Strategy

• Hamamatsu, for example, will deliver 200
  PMTs/month. We need 14.3 months.
• PMTs will be supplied with gain of 3x105 with
  gain measurements at 1300, 1500 and 1650 V by
  Hamamatsu.
• The cost estimate is 690 K based on 110 Yen/.
• Sole source or bidding? There are several PMTs
  that would do the job.
• We should be able to test at the same rate as
  production, i.e. 10 PMTs/day, on average.
• The PMT responsibilities are with Iowa, ISU and
  Fairfield.

22
Milestones

• Draft RFP March.15.01
• Evaluate samples May.15.01
• PMT test station ready August.15.01
• Final contract signed September.15.01
• Delivery 1st batch 100 PMTS November.1.01
• Delivery last batch January.1.03
• Assuming delivery of 200-300 PMTs after 3
  months of receiving order. Then delivery 200-300
  PMTs per month as last batch delivered by
  January 1, 2003.
• We budget total of 1 hour to unpack, test,
  label, repack, and enter, merge publish archive
  data 2700 PMT. The selection database will be
  maintained for each PMT together with the base
  and front end electronics.

23
Tube Base

• Prototype completed end of January
• Cockroft-Walton multiplier style base
• Series resonant sine-wave converter invented by
  Claudio Rivetta and implemented by Sten Hansen
  (Fermilab)
• Very low noise
• Low power consumption
• Last dynode voltage sags 0.5 V from 0 to 200
  microamps factor of 20 headroom for the hottest
  tubes at eta 5
• Iowa State and Texas Tech Universities
  responsible for specifications and testing

24
Tube Base Prototype
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Conclusions

• We had PRR at CERN in Feburary
• We have evaluated the performance of the
  candidate PMTs
• RFP is drafted and we expect to sign the final
  contract in early September
• We have designed the PMT test station and built a
  small prototype version to evaluate the candidate
  PMTs.
• Computer controlled x-y scanner and neutral
  density fibers are built and presently under test
• Major components of the final PMT station and
  related electronics are purchased and the system
  will be ready by mid-August
• Design of CW bases are in progress at FNAL
• The PMT readout project is on time and budget