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TEST BEAM 2009: situation. latest test: calibration: led HERAB and RLS-UV395 results npe vs gas pressure (for different gases) angular scan efficiency vs quartz window double tracks Open problems sigma/mean decreases in the pressure scan. Bologna 4/11/2010.
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TEST BEAM 2009: situation • latest test: calibration: led HERAB and RLS-UV395 • results • npe vs gas pressure (for different gases) • angular scan • efficiency vs quartz window • double tracks • Open problems • sigma/mean decreases in the pressure scan Bologna 4/11/2010
FADC signal: peak position inside the gate LED HERAB RLS-UV395 >90% of evts in 4 bins (16 ns) FADC sampling FADC sampling LED RLS-UV395 Position of the signal is stable and the % of double peaks decreases LED HERAB Position of the signal ranges in all gate
Calibration constant values averaged on all the inputs voltage of the led RLS-UV395 LED HERAB * The error is the range/sqrt(12) compatibility inside 10% (remember: the electronics is very simple in both cases and different from the test beam)
Calibration with cosmic signals (V=1250 V) CERN2 CERN1 DESYMY CERN3
Cosmic signals: npe Unbinned likelihood fit with gaussian plus explonential evaluated on the cosmic peak ~ expected region but the range is wide (in my opinion)
Results for publication (eventual) • results • npe vs gas pressure (for different gases) • angular scan • efficiency vs quartz window • double tracks • Open problems • sigma/mean decreases in the pressure scan
CERN1: press scan FADC Press scan evaluated by the integral charge of the FADC 2 PROBLEMS sigma Integral charge Volt• ns Npe at 150 mbar (from cosmic) vary of a factor 2 between the pmts SAME PROBLEM AS QDC NOT UNDERSTOOD Similar for all the other pmts (see backup slides)
C4F10 Isob N2 Pressure scan CERN1 CERN2 CERN3 pressure pressure pressure CERNRAW DESYMY DESYMP pressure pressure pressure
Angular scan: CERN3 CERN3 with gas CERN3 without gas Mean = (-1.5±0.1) mm About 1 mrad shift 9
PMT mm 7 Study inside the pmt efficiency vs distance from the pmt center
CERN1: Efficiency, amplitude and sigma inside the pmt Detection efficiency amplitude sigma 150 mbar Probably the width of the pmt is not uniform 1.1 bar Similar for all the other pmts (see backup slides)
Two tracks: example CERN1 run 5889 Without any selection Cut: tracks in pmt (r<7 mm) Peak and sigma scale as expected
summary • calibration • Single photoelectrons method OK • rms2/mean•const from LED signal NO • npe ofcosmic signal till a difference of a factor 2 • results • npe vs gas pressure (for different gases) diff of 2 • angular scan OK • efficiency vs quartz window OK • double tracks OK • Open problems • rms2/mean•const from LED signal • sigma/mean decreases in the pressure scan
Pressure scan CERN1 and CERN2 : sigma sigma sigma sigma C4F10 N2 ISOB CERN1 pressure pressure pressure C4F10 N2 ISOB CERN2 pressure pressure pressure
Pressure scan CERN3 and CERNRAW : sigma sigma sigma sigma C4F10 N2 ISOB CERN3 pressure pressure pressure C4F10 ISOB N2 CERNRAW pressure pressure pressure
Pressure scan DESYMY and DESYMP : sigma sigma sigma sigma C4F10 N2 ISOB DESYMY pressure pressure pressure C4F10 DESYMP pressure
CERN2: Efficiency, amplitude and sigma inside the pmt Detection efficiency amplitude sigma 150 mbar 1.1 bar
CERN3: Efficiency, amplitude and sigma inside the pmt Detection efficiency amplitude sigma 150 mbar 1.1 bar
CERNRAW: Efficiency, amplitude and sigma inside the pmt Detection efficiency amplitude sigma 150 mbar 1.1 bar
DESYMP: Efficiency, amplitude and sigma inside the pmt Detection efficiency amplitude sigma 150 mbar 1.1 bar
DESYMY: Efficiency, amplitude and sigma inside the pmt Detection efficiency amplitude sigma 150 mbar 1.1 bar