Cathode Voltage Effect on the Peak sensing Spectrum

All the measurements have the same GEM voltage 2.87 kV, just cathode voltage changes.

GEM-2.87 kV CATH-3.435 kV

Date	Shutter	source	run number	Scaler counts (Hz)	pedestal	Integral in ADC full spectrum (Hz)	Integral in ADC spectrum beyond pedestal (Hz)	notes
10/16	Open	off	7847	150+_7	1429/60	7915/60	5810/60
10/16	Closed	off	7846	72+_3	1070/60	4029/60	2817/60
10/16	Open	off	7848	137+_16	19	129	111
10/16	Closed	off	7862	53+_1	7	47	41
10 /16	Open	On	7863	147+_12	30	129	101
10/16	Closed	On	7864	67+_4	15	59	45
10/17	Open	off	7865	132+_14	28	121	97
10/17	Closed	off	7866	95+_7	11	59	49
10 /17	Open	On	7868	150+_6	32	128	100
10/17	Closed	On	7867	74+_4	13	63	52
10/18	Open	off	7872	136+_10	9	124	115
10/18	Closed	off	7871	51+_3	4	48	44
10 /18	Open	On	7869	140+_10	10	123	115
10/18	Closed	On	7870	53+_2	4	49	44
10/19	Open	off	7873	124+_14	10	114	104
10/19	Closed	off	7874	59+_4	5	54	49
10 /19	Open	On	7876	141+_8	10	117	108
10/19	Closed	On	7875	60+_4	6	55	50
10/20	Open	off	7879	129+_16	8	116	108
10/20	Closed	off	7880	49+_2	2	45	42
10 /20	Open	On	7882	142+_3	8	108	99
10/20	Closed	On	7881	53+_2	5	49	44

Date	Shutter	source	run number	Notes
10/21	open	off	7884	5 min separate pedestal from signal
10/20	Closed	off	7885	5 min shows a difference.
10/22	open	off	7891	5 min CATH 2930 V
10/22	Closed	off	7892	5 min CATH 2930 V
10/22	open	off	7893	2 min CATH 3435 V
10/22	Closed	off	7894	2 min CATH 2435 V
10/23	open	off	7898	5 min CATH 3435 V low shutter close rate
10/23	Closed	off	7897	5 min CATH 2435 V
10/23	open	off	7902	min CATH 3435 V
10/23	Closed	off	7901	2 min CATH 2435 V

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