MINERvA M64 PMT Test Stand: A proposal

1
MINERvA M64 PMT Test Stand A proposal
George S. Tzanakos Physics Department, University
of Athens, Greece

• Goal Build a Test Stand that can test and
  characterize 10 PMTs in less than two days.
• Assumptions about MINERvA Electronics
• PMT Test Stand can be supported with 11x 64
  channels of ADCs
• DAQ rate 500 Hz
• Integration Time 12 ?s

2
HV cables
6 PMTs
HV controller
Multiplexer
Stage Controller
Stages-Filter Wheel
special protocol
LED pulser
TCP/IP
signal cables
Trigger Unit
SCSI bus
VME bus
MINERvA Electronics (ADCs)
3
11 PMTs per batch 64 bundles of 11 fib
x,y stages
4
DARK COUNTS 1 sec ? 500 windows of 12 ?s ?
0.006 s of live time 1hr ? 21.6 s live time, For
a DC rate of 250Hz ? 5400 DC total Assume a 2 hr
collection ? 10800 counts total ? 170
counts/channel OPERATING HV 5 HV settings (-750,
-800, -850, -900, -950 ), 64 positions, 5000
pulses/ position, 10 sec movement time, HV
Settling ? 5 hrs (Oxford) Spe Response, Gain
uniformity, Linearity, Xtalk 12 filters, 64
positions, 10000 light pulses per setting ? 13
hrs (Oxford) TOTAL 2513 20 hrs per complete
cycle
5

• Assume
• 4 hrs preparation of new batch and processing of
  previous batch
• 4 hrs for PMT settling
• 2 cycles of testing
• We get
• TOTAL TESTING TIME FOR 10 M64s 442020 48
  hrs
• CONCLUSION
• With the assumptions made, we need 2 days for 10
  MINERvA PMTS