histogram analysis Shutter Open - Closed in LDS Lab
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.
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!
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
which peak is Beta?
Run 5200 has a shift more the other runs, the run represented the charge collected as the shutter is close. Averaging three runs as the shutter is open, then subtracting 5200 are represented by the following figures.
Run 4676 :Average of normalized shutter Open ADC spectrum
Run 5200 normalized, shutter closed ADC spectrum
subtracting close from open
Relative Gain increase
I increased the voltage 50 volts and I had to attenuate 8 db this means that a 50 volt increase in the GEM pre-amplifier resulted in a gain increase of ?.
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