Difference between revisions of "Threshold & HV study"
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| Line 16: | Line 16: | ||
! <math>n_{0}</math> rate | ! <math>n_{0}</math> rate | ||
!noise | !noise | ||
| + | !<math>n_{0}</math>/noise | ||
! run # | ! run # | ||
! PMT <br>threshold | ! PMT <br>threshold | ||
| Line 22: | Line 23: | ||
|- | |- | ||
!D30 | !D30 | ||
| − | | | + | | n0 |
| − | | | + | | noise |
| + | |n0/nois | ||
| rowspan="4" | r5242 | | rowspan="4" | r5242 | ||
| rowspan="4" | 25 | | rowspan="4" | 25 | ||
| Line 29: | Line 31: | ||
|- | |- | ||
!D90 | !D90 | ||
| − | | | + | | n0 |
| − | | | + | | noise |
| + | |n0/nois | ||
|- | |- | ||
!D150 | !D150 | ||
| − | | | + | | n0 |
| − | | | + | | noise |
| + | |n0/nois | ||
|- | |- | ||
!D225 | !D225 | ||
| − | | | + | | n0 |
| − | | | + | | noise |
| + | |n0/nois | ||
|- | |- | ||
Revision as of 21:57, 29 August 2016
Overview
A series of triggered CF-252 runs are conducted at various detector PMT high voltages and discriminator thresholds. A TDC spectrum is acquired using daq2 so that a neutron cut can be applied. These data provides us with a relationship between neutron detection rate and PMT HV/threshold.
Setup
A CF-252 source along with a trigger scintillator is placed at the geometric center of the array of neutron detectors. The source discriminator threshold is kept constant throughout the study at 100 mV.
Pulses from the source trigger are delayed by 1500 ns and serve as the common stop time for the TDC.
An event is considered a neutron detection if both PMT top and bottom saw a hit and the resulting ToF also lies in the neutron range.
results
| Detector | rate | noise | /noise | run # | PMT threshold |
HV |
|---|---|---|---|---|---|---|
| D30 | n0 | noise | n0/nois | r5242 | 25 | 1700 |
| D90 | n0 | noise | n0/nois | |||
| D150 | n0 | noise | n0/nois | |||
| D225 | n0 | noise | n0/nois | |||
| D30 | ? | ?? | r5239 | 30 | ||
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? | ||||
| D30 | ? | ?? | r5240 | 35 | ||
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? | ||||
| D30 | ? | ?? | r5241 | 40 | ||
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? | ||||
| D30 | ? | ?? | r5243 | 25 | 1650 | |
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? | ||||
| D30 | ? | ?? | r5244 | 30 | ||
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? | ||||
| D30 | ? | ?? | r5245 | 35 | ||
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? | ||||
| D30 | ? | ?? | r5246 | 40 | ||
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? | ||||
| D30 | ? | ?? | r5247 | 25 | 1600 | |
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? | ||||
| D30 | ? | ?? | r5248 | 30 | ||
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? | ||||
| D30 | ? | ?? | r5249 | 35 | ||
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? | ||||
| D30 | ? | ?? | r5250 | 40 | ||
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? | ||||
| D30 | ? | ?? | r5251 | 25 | 1550 | |
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? | ||||
| D30 | ? | ?? | r5252 | 30 | ||
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? | ||||
| D30 | ? | ?? | r5253 | 35 | ||
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? | ||||
| D30 | ? | ?? | r5254 | 40 | ||
| D90 | ? | ?? | ||||
| D150 | ? | ?? | ||||
| D225 | ? | ?? |