1. Yanhong Yu, Cunfeng Feng
CR285 PMT performance
Yanhong Yu, Cunfeng Feng
SDU
2017/09/14

2. SP, SK method compare with SPE Gain
SP/SK provide by the Hamamatsu company.
Gain is test results from SDU using SPE method, this results from Ang Li’s experiment notebook
The Gain from SPE method is almost double of SP/SK
PMT No.
(10^6）
（10^6）
Gain/(SP/SK)
A67689
1.60
3.07
1.92
A67749
2.38
4.59
1.93
A67693
2.02
4.17
2.06
A67748
1.35
2.26
1.67
A67752
3.05
6.90
SPE method:
1, measure the single photoelectron peak at 1200V, and get the Gain at 1200V: G=(QCDspe-QCDpedestal)*(charge per QDC channel)/(1.6E-19)
2, fit the parameter a and b of formula G=AV^β:
(1)measure the charge of PMT output at 1200V, 1100V, 1000V, 900V，800V，700V.
(2) fit the charge~voltage by formula G=AV^β, then acquire A and β value.
3, A*(1000)^ β
plot of voltage and PMT output charge.

3. Wave form of PMT A67689 PMT voltage 1000V
Wave form at higher light intensity
Wave form at low light intensity. Peak is 1.6V, width=30ns
Charge around (1.6V/50Ω)*30ns/2=480pC,
NPE=480pC/((1.6E-7pC)*(G=3.07E6))= 977(SPE method)
NPE=480pC/((1.6E-7pC)*(G=1.6E6))=1875 (G=SP/SK)

4. Wave form of PMT A67689
Fixed light intensity
PMT voltage at 1000V,1100V, 1200V
1200V
1000V
1100V

5. PMT linear dynamic range test
nonlinearity(%)
High voltage：900V，
Max Non-linearity current: 20.1mA.
current (mA)
High voltage：1000V,
Max Non-linearity current：17.2mA.
17.2mA*30ns/2=228pC
NPE=228pC/(e*G)
=228/(1.6*3.06*0.1)=467 (SPE)
or =228/(1.6*1.6*0.1)=891 (SP/SK)
High voltage：800V
Max Non-linearity current ：17.0mA.

6. Zoom of above plot

7. Here is how non-linearity of the PMT gain is defined
Detail: arXiv: