GEM performance data graphs

histogram analysis Shutter Open - Closed

GEM detector voltage settings:

Discriminator:

Amplification:

Shutter open run 4676 took data for 44480 seconds (12.4 hrs) and Shutter closed run 4675 took data for 28638 seconds (8 hrs)

Run 4676 :raw shutter Open ADC spectrum	Run 4675 raw shutter closed ADC spectrum
Run 4676 :NORMALIZED shutter Open ADC spectrum	Run 4675 NORMALIZED shutter closed ADC spectrum

Assume that the single peak for the Closed shutter spectrum is the result of less charge being liberated by the right most peak of the shutter open spectrum due to the energy lost by the ionizing particle as it travels through the 1mm thick FR4 shutter into the ionization chamber.

Run 4676 :raw shutter Open ADC spectrum	Run 4675 raw shutter closed ADC spectrum

Shutter Open - Shutter Closed Difference

Run List1 GEM, Cathode 2.6, 2.9kV

/home/daq/CODA/CODAreader/ROOT_V5.30/V775mV792/evio2nt -fr4685.dat > /dev/null

The voltage of the Cathode is 2.9 kV and of the GEMs is 2.6 kV.

The amplifier is on x6 level fine gain which will amplify the detector signal to 33.5 times (6.56+_ 0+_ V/196 +_ 0.6mV).

Run #	discrimination level	ortec 474 amplification	Start Date	End Date	Shutter Position	Source	pulse snapshot picture and Comparison notes
4662	0.25	4	17:00 04/04	10:00 04/05	open	off
4663	1.1	4	10:00 04/05	13:14 04/05	open	off
4664	0.9	4	13:14 04/05	16:48 04/05	open	off
4665	0.9	4	17:11 04/05	20:21 04/05	open	on
4666	1.1	4	20:26 04/05	21:38 04/05	open	On
4668	0.25	6	21:47 04/05	7:45 04/06	open	off	compare ampx4 (blue) and ampx6 (red) ortec #of counts 1.37M, ADC # of counts 676056
4670	0.25	4	11:00 04/05	11:55	closed	On
4671	0.25	6+ fine level 3	12:28:38 04/06	12:38	closed	off
4672	0.25	10	12:38:28 04/06	12:42	closed	off
4673	0.25	6+fine level 5	12:42:59 04/06	12:47:30	closed	off
4674	0.25	6+fine level 4.5	12:48:18 04/06	13:01:50	closed	Off
4675	0.25	6+fine level 4.5	13:03:35 04/06	21:00:55	closed	Off
4676	0.25	6+fine level 4.5	21:06:07 04/06	09:27:29 04/07	open	Off	compare shutter open (blue) and shutter close (red)
4677	0.25	6+fine level 4.5	09:31:03 04/07	21:31:07 04/07	open	on	compare shutter open as the source is off(blue) and as it is on (red)
4678	0.25	6+fine level 4.5	21:32:10 04/07		close	on
4679	0.25	6+fine level 4.5	10:39:19 04/08	22:22:21 04/08	close	off
4680	0.25	6+fine level 4.5	22:26:10 04/08	10:05:07 04/09	open	off
4681	0.25	6+fine level 4.5	10:08:59 04/09	14:26:12 04/09	open	on
4682	0.25	6+fine level 4.5	14:30:43 04/09	06:51:39 04/10	open	off
4683	0.25	6+fine level 4.5	06:56:00 04/10	16:07:36 04/10	close	off	compare r4683 (red) and r4679 (blue) as both have hsutter is close without source
4684	0.25	6+fine level 4.5	16:10:59 04/10	10:46:10 04/11	close	off	compare r4684 (red) and r4683 (blue) as both have hsutter is close without source
4685	0.25	6+fine level 4.5	10:50:52 04/11	07:06:55 04/12	open	off	r4685 (blue) has the two peaks close in height compared to the other two runs (r4682(red) and r4676(green), which indicates that the source has a new source of charge as result of a decay to one of the short half life alpha emitting daughters.
4686	0.25	6+fine level 4.5	07:37:34 04/12	19:50:55 04/12	close	off	comparing three runs together r4686(blue),r4684(red), and r4679 (green). they are all record the charge as the shutter is close. it is noticed that the last run reproduced the expected peak that was observed before in r4679
4687	0.25	6+fine level 4.5	19:54:17 04/12	06:59:28 04/13	open	off
4688	0.25	6+fine level 4.5	07:01:35 04/13	10:31:31 04/13	open	off
4689	0.25	6+fine level 4.5	10:33:13 04/13	19:09:56 04/13	close	off	the new peak (in 4688) was partial blocked by the shutter but the tail is still high compared to 4686.
4690	0.25	6+fine level 4.5	19:26:44 04/13	06:41:16 04/14	open	off
4691	0.25	6+fine level 4.5	21:15:44 04/13	09:58:16 04/14	open	off
4692	0.25	6+fine level 4.5	10:05:14 04/15	16:34:50 04/15	open	off	back to the normal spectrum as the shutter is open
4693	0.25	6+fine level 4.5	16:41:05 04/15	07:29:25 04/15	close	off
4694	0.25	6+fine level 4.5	07:39:30 04/16	14:51:29 04/16	close	off
4694	battery		battery charged collected by the ADC without any electronics used1
4695	battery		battery charged collected by the ADC as the battery charge passes through the NIM-modules
4914	0.57	6+fine level 4.5	13:39:25 04/30	07:26:42 05/01	open	off
4917	0.36	6+fine level 4.5	10:00:21 05/01	14:43:05 05/01	open	off
4918	0.36	6+fine level 4.5	14:53:41 05/01	13:56:05 05/01	open	on
4935	0.36	6+fine level 6	16:38:38 05/01	07:30:04 05/02	open	off
4936	0.36	6+fine level 6	07:34:01 05/02	15:02:30 05/02	close	off
4989	0.36	6+fine level 6	11:47:06 05/03	15:40:47 05/03	close	off	10Hz
4990	0.36	6+fine level 6	15:44:10 05/03	22:36:28 05/03	open	off	10Hz
4992	0.36	6+fine level 6	22:57:47 05/03	08:51:26 05/04	close	off	100Hz clock
5078	0.5	6+fine level 6	20:39:35 05/08	06:09:23 05/09	open	off	10Hz
5079	0.36	6+fine level 6	06:47:58 05/09	14:26:08 05/09	open	off	10Hz
5091	0.36	6+fine level 6	16:25:48 05/09	21:21:11 05/09	close	off	without clock
5092	0.36	6+fine level 6	21:26:23 05/09	06:23:34 05/10	open	off	10 clock
overlayed plots need to be normalized to the running time!	sure		comparing 4691 (light brown),4690(blue),4687 (red),4676 (green),4685 (purple)

Run List2 GEM,Cathode 2.65,2.95kV

The voltage of the Cathode is 2.95 kV and of the GEMs is 2.65 kV.

Run #	discrimination level	ortec 474 amplification	Attenuation (dB)	Start Date	End Date	Shutter Position	Source	pulse snapshot picture and Comparison notes
5061	0.40	6 level 6	6	12:15:47 05/04	18:16:57 05/04	close	off	10Hz
5062	0.40	6 level 6	6	18:23:41 05/04	16:12:20 05/05	open	off	10Hz
5063	0.40	6 level 6	8	16:18:02 05/05	22:55:20 05/05	open	off	10Hz
5064	0.40	6 level 6	8	22:59:02 05/05	07:32:26 05/06	open	on	10Hz
5065	0.40	6 level 6	8	07:37:17 05/06	12:39:17 05/06	close	on	10Hz
5066	0.40	6 level 6	8	02:43:55 05/06	17:44:20 05/06	close	off	10Hz
5198	0.96	6 level 6	8	18:12:00 06/03	00:05:32 06/04	open	off	700Hz
5200	0.96	6 level 6	8	00:08:49 06/04	07:19:28 06/04	close	off	10Hz
5204	0.96	6 level 6	8	09:33:45 06/04	14:31:49 06/04	open	off	10Hz
5215	1.55	6 level 6	8	16:04:59 06/04	20:15:59 06/04	close	off	10Hz
5224	1.25	6 level 6	8	21:45:45 06/04	07:12:49 06/05	open	off	10Hz
5225	0.96	6 level 6	8	7:15:51 06/05	07:12:49 06/04	open	off	10Hz

Run List3 GEM,Cathode 2.7,3kV

Calibration curve

,Measurements

The voltage of the Cathode is 3 kV and of the GEMs is 2.7 kV. Without any attenuation -85 mV was the initial voltage and its equivalent charge is 1.02 nC. According this value the charge below is calculated using

[math] Q = Q_0 10^{(L_v/20)} [/math]

Run #	discrimination level	ortec 474 amplification	Attenuation (dB)	Start Date	End Date	Shutter Position	Source	pulse snapshot picture and Comparison notes	Channel number	ADC charge (nC)	Detector charge (nC)
5072	0.50	6 level 6	11	18:20:09 05/06	22:28:25 05/04	open	off	10Hz	1650 , 3500	0.766, 1.506	7.7, 15.06
5073	0.50	6 level 6	11	22:31:50 05/06	06:09:58 05/07	open	on	10Hz
5074	0.50	6 level 6	11	06:16:00 05/07	12:39:58 05/07	close	on	10Hz
5075	0.50	6 level 6	11	12:45:04 05/07	07:58:00 05/08	close	off	10Hz
5076	0.50	6 level 6	11	08:00:44 05/08	13:06:40 05/08	open	off	10Hz
5077	0.50	6 level 6	11	13:09:56 05/08	20:27:39 05/08	close	off	10Hz
5273	1.66	6 level 6	11	22:51:57 06/07	05:43:14 06/08	open	off	10Hz
5076	1.66	6 level 6	11	06:05:48 06/08	10:57:48 06/08	close	off	10Hz 90px

Run List 4 GEM,Cathode 2.75,3.05kV

Run #	discrimination level	ortec 474 amplification	Attenuation (dB)	Start Date	End Date	Shutter Position	Source	pulse snapshot picture and Comparison notes	Channel number	ADC charge (nC)	Detector charge (nC)
5228	1.29	6 level 6	15	10:26:45 06/05	14:48:25 06/05	open	off	10Hz
5229	1.29	6 level 6	15	14:49:16 06/05	19:11:06 06/05	close	off	10Hz
5230	1.29	6 level 6	15	19:12:39 06/05	04:08:00 06/06	open	off	10Hz
5235	1.29	6 level 6	15	04:10:19 06/06	07:35:30 06/06	close	off	10Hz
5236	1.29	6 level 6	15	07:36:39 06/06	10:04:15 06/06	open	off	10Hz
5237	1.29	6 level 6	15	10:06:54 06/06	14:51:54 06/06	close	off	10Hz

Run List 5 GEM,Cathode 2.8,3.10kV

Run #	discrimination level	ortec 474 amplification	Attenuation (dB)	Start Date	End Date	Shutter Position	Source	pulse snapshot picture and Comparison notes	Channel number	ADC charge (nC)	Detector charge (nC)
5261	1.63	6 level 6	17	17:10:06 06/06	21:41:15 06/06	close	off	10Hz
5262	1.63	6 level 6	17	21:43:02 06/06	05:53:12 06/07	open	off	10Hz
5263	1.63	6 level 6	17	17:10:06 06/06	09:51:53 06/07	close	off	10Hz
5264	1.63	6 level 6	17	09:52:59 06/07	14:22:56 06/07	open	off	10Hz
5265	1.63	6 level 6	17	14:24:31 06/07	17:52:16 06/07	close	off	10Hz
5266	1.63	6 level 6	17	18:02:41 06/07	22:23:11 06/07	open	off	10Hz

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