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Details of Analysis of PSI beam test. R.Sawada 21/1/2004 on VRVS. Event Selection and Q.E. correction. & (NaI sum)<105. This cut is not important , because resolution doesn’t change with this cut. Q.E. estimated from liquid data was used for each PMT. 1st Step (remove pedestal events).
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Details of Analysis of PSI beam test • R.Sawada • 21/1/2004 • on VRVS
Event Selection and Q.E. correction & (NaI sum)<105 This cut is not important , because resolution doesn’t change with this cut. Q.E. estimated from liquid data was used for each PMT.
1st Step (remove pedestal events) Mainly, subtraction of pedestal events. 367k events 267k events
2nd Step (83 MeV gamma rejection) & (NaI sum)<105 FWHM = 8.5 ± 0.3 % 82k events (34k events Qsum>25000)
3rd step (position selection) FWHM = 7.9 ± 0.9 % I used simple average, if I use iteration method this figure will be more beautiful, but I have not done. Probably energy resolution doesn’t change. 7160 events (4223 events Qsum>25000)
4th step (depth selection) 3077 events (2059 events Qsum>25000) FWHM = 4.9 ± 0.4 %
5th step (depth correction) FWHM = 4.5 ± 0.4 % 3077 events (2059 events Qsum>25000)
6th step (reject z<0) data FWHM = 4.5 ± 0.4 % MC 2001 events (1993 events Qsum>25000) red points: z of conversionpoint < Front face
# of events (Qsum>25000) FWHM [%] all 367k step1 Mainly,removal pedestal events. 267k step2 removal 83 MeV 82k(34k) 8.5 ± 0.3 step3 x-y selection 7160(4223) 7.9 ± 0.9 step4 depth cut 3077(2059) 4.9 ± 0.4 step5 depth correction same 4.5 ± 0.4 step6 cut of z<0cm 2001(1993) 4.5 ± 0.3 Number of Events
Qsum dependence on x-y w/ depth cut w/o depth correction Combined analysis with all x-y position data has not be done yet. It seems that we need energy calibration for each point to obtain 4.5 level resolution. (We will be able to use Pi0 decay for calibration of the final detector)
# of events all (#7045) 48472 step1 100<(TDC of TCi)<4000 7934 step2 (ADC of TCi) > thresold 6724 step3 25000< sum< 34000 1251 step4 at least , one PMT observes more than 20 nphe. 1178 step5 sigma2<90 & Nfpmt(0.5)>4 349 step6 # of PMTs which observes more than 20 nphe > 180 259 Event selection (Timing) step 6 is applied only for (Xe-TC) Analysis threshold: TC1>150ch, TC2>200ch, TC3>140ch, TC4>140ch
ADC cut of Timing counter TC1 TC2 TC3 TC4
for Review meeting • Energy Resolution of 83 and 129 MeV (including alpha and TERAS results). • Other masking to simulate in case that we have only 600 PMTs. • 1/2 of back,top,bottom • 1/4 of left,right