CMS HF PMT SYSTEM

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CMS HF PMT SYSTEM
By Y. ONEL U. of Iowa, Iowa City, IA HF-RBX
PRR CERN Apr 3-4, 2003
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CMS-HF PMT Test and Quality Control System
U. Akgun1, A.S. Ayan1, F. Duru1, E. Gulmez2, M.
Miller1, J. Olson1 Y. Onel1, I. Schmidt1 with
Quarknet Group P. Bruecken, C. Like, R. Newland
1 University of Iowa, Iowa City, USA 2 Bogazici
University, Istanbul, Turkey
Abstract We have measured the specifications
proposed by the CMS-HCAL committee on the
candidate phototubes from the three major
manufacturers Hamamatsu, EMI and Photonis. In
this report, we present the results from those
measurements and we outline the future
measurements for the test and the quality control
as well as the design of the new University of
Iowa PMT test station facility.
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Tasks of the Test System

• For one tube in every batch
• Double-pulse linearity,
• Gain vs HV for each batch
• Single photoelectron spectrum
• X-Y scan (spatial uniformity)
• Lifetime
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• For each tube
• Pulse width
• Pulse rise time
• Transit time
• Transit time spread
• Anode dark current
• Relative gain coupled with cathode sensitivity,
• Pulse linearity
• Quality control decision on each tube.

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UNIVERSITY of IOWA PMT TEST STATION
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LabVIEW software
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PMT Timing Data (1900 PMTs)
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PMT Timing Data (1900 PMTs)
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PMT Data (1900 PMTs)
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CA0058 Double Pulse Linearity
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Double Pulse Linearity Results on 10 PMTs
Note Statistical error is 0.9
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Single Photoelectron Spectrum at 1100V
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Single Photoelectron Spectrum at 1500V
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XY Uniformity
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Definition of Relative Gain and Gain

• Relative Gain (Normalized Output)
• Anode output of a PMT when exposed to the same
  light intensity (2) as the Reference PMT and
  normalized with respect to the output of the
  Reference PMT
• For each PMT, Reference PMT is also tested.
• Gain
• Anode output current / Cathode output current

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Relative Gain vs Gain
CONCLUSION We can sort pmts w.r.t. their
Relative Gain values
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Gain vs HV for Relative Gain 50-70
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Lifetime Measurement Setup
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Timing characteristics after 1100 C

• After more than 1100 C of charge accumulation
• - No change in timing properties.
• Gain dropped to 70 of initial value.
• Experiment is still on.

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PMT Web Database
Sort by column (Ascending or Descending)
Alternating colors to aid readability
Pagination reference for large data sets
More extensive search/sort options are being
developed
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PMT Web Database
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