ECAL_test_Dec_2011 INR, Moscow

Standard test bench for ECAL modules test

σ= 5.47% RUN DAT HV 1400 V RUN DAT HV 1350 V σ = 6.43% Measurements with standard electronics ….good agreement with previous Yu.Sobolev measurements

CAEN DT bit 5 GS/s Switched Capacitor ADC PC Replacement standard ADC on Replacement standard ADC on CAEN DT5742

Module 8, HV 1350 V Module 8, HV 1400 V σ= 6.9% σ= 5.4% Practically the same results with new CAEN ADC and standard ADC

CAEN DT bit 5 GS/s Switched Capacitor ADC PC Direct measurements of amplitude and charge of the PMT signal using of the PMT signal using CAEN DT5742

Module 8, HV 1350 V The shape of the signal after PMT PMT EMI-9903KB Resolution of amplitude distribution is worse than charge one due to peaks on the shape of signal

CAEN DT bit 5 GS/s Switched Capacitor ADC PC TOFINO shaper Measurements of amplitude of the PMT signal using of the PMT signal using CAEN DT5742 and TOFINO shaper

Energy resolution (%) for module #8 measured by different methods TOFINO Shaper +CAEN ADC Without shaper (CAEN ADC) ADC QDC GSI Shaper+ CAEN ADC GSI Shaper MA ORTEC ADC Method HV(V) Pavel Tlusty: I did similar with the Yokogawa oscilloscope, which also samples the signal. What I found was that I get better resolution after shaping the signal by the MA8000 shaper. Without the shaper, the resolution, both on ADC and QCD was about 10%. With the shaper it was 6.5% == exactly the same as with our ORTEC ADC.

Conclusion Measurement of energy resolution of one of the ECAL module has been done on cosmic using different methods and electronics. Significant difference is found in resolution between direct measurements of amplitude and charge of the signal and resolution measured by using standard electronics with GSI shaper. ADC resolution measured by using TOFINO shaper gives the same result as direct measurements of QDC resolution without shaper. These results confirms our measurements on cosmic we have done at the end of Here we got resolution about 12% by direct measurement of charge using LeCroy QDC. Unfortunately, we have not enough time to do the same measurement with HAMAMATSU PMT (from TOFINO). This is planned to do in Feb

TO DO list Feb_March_ The same measurements on cosmic with HAMAMATSU PMT(2’’) and new PMTs frpm Laura (3’’). with standard electronics and CAEN sampling ADC. PMTs frpm Laura (3’’). with standard electronics and CAEN sampling ADC. 2. Use new electronics from Poland?