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

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. SP/SK@1000V (10^6） gain@1000V （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, Gain(@1000V)= A*(1000)^ β plot of voltage and PMT output charge.

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)

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

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.

Zoom of above plot

Here is how non-linearity of the PMT gain is defined Detail: arXiv:1512.02739