Another look to the BGO matrix calibration C.Voena INFN Roma

PowerPoint Presentationcalibration
As in the paper, event by-event for PMTi
(start of signal is determined from average time profile):
Qi = Integral[0,115]ns
Si = Integral[50,115]ns
S1/S2=27%
sample
mV
S2
S1
*
Qsum
central beam position
Qsum
Q1
- Strange distributions at Y>0 and for some runs also at Y<200 and Y>-200 (Y= vertical coordinate of downstream beam chamber)
- The tails of Qsum distribution are concentrated at Y>0
Cut at Y<0 and Y>-200 in what follows
Y(tdc counts)
Y(tdc counts)
Calibration procedure using Qi: minimize resolution
Intercalibration constants k1i of all runs at 10-20-30-50-100-150-200 GeV at the three different position (21 runs) by minimizing:
j=run number
in position c
-1/√E(GeV)
Qsum
- Very non uniform behavior with respect to central position
- beam position a) is in better agreement with central
beam position
0.8-1.2 range for all positions
Resolution
Linearity
-1/√E(GeV)
for C and S improve resolution of few %.
*
Linearity
for C and S improve resolution of few %.
*
at all energies
- Resolutions for beam in central position
- Linearity at <5% level except at 10GeV and 20-30 GeV
for Cerenkov signal
- Very different response when beam is sent in position c)
- Some improvement in resolution with respect to approach
that minimizes linearity but worse linearity for Cerenkov
signal