From RHESSI Wiki
This page contains information about changes/issues for RHESSI detector 6 after the 2014 anneal. Detector updates from 2012-mid 2014 can be found here: Detector 6 anneal 2012
Notes
After the 2014 anneal, detector 6 began its reincarnated life as an unsegmented detector but segmented shortly after (see below).
- On 2014 August 14, the HV on D6 was raised to 4926V in an attempt to segment it. This was successful, and D6 now operates as a segmented detector. Since its segmentation is borderline as of Aug/Sept 2014, it commonly unsegments during and just after the SAA.
- On 2014 Jan 8, the rear fast threshold was raised since fast counts were eating up a lot of livetime.
15-008-17:44:55 /IDPUTABLE6 OFFSET=REARFASTDAC
15-008-17:45:18 /IDPULOAD VALUE=0x50 ;(was 0x45)
- * D6 has been showing some strange peaks in the spectrum; these are best seen as multiple lines (that drift) in spectrograms. On Monday, Jan 28 we raised the slow front threshold on D6 to ~10 keV and kept it there for a day before returning to the nominal ~3 keV. This is intended to see if the slow threshold affects the abnormal spectral lines.
15-026-21:57:13 / D6 front slow threshold to 0x30 (was 0x0C).
15-027-21:37:03 / D6 front slow threshold to 0x0C (was 0x30).
- D6 fast rates are a bit high (have been rising slowly over the past week). It would be a good idea to raise the front fast threshold a touch. I didn't want to do this at the same time as the slow threshold experiment!
- D6 front fast threshold was adjusted from default (0x22) due to increased rates, based on the above suggestion. Rates dropped from 3300 to 1250 when the change was made.
15-030-00:19:54 /IDPUTABLE6 OFFSET=FRONTFASTDAC
15-030-00:20:17 /IDPLOAD VALUE=0x30 ; was 0x22
- On 2015 February 27 Front Fast threshold was raised
15-058-21:41:11 /IDPUTABLE6 OFFSET=FRONTFASTDAC
15-058-21:41:44 /IDPLOAD VALUE=0x40 (was 0x30)
- Another raise to D6 front fast threshold on 2015 March 9:
15-068-01:26:56 /IDPUTABLE6 OFFSET=FRONTFASTDAC
15-068-01:27:07 /IDPLOAD VALUE=0x50
- On 2015 March 13 another raise was made to D6 front fast threshold and a raise of the rear fast threshold was made:
15-072-22:04:01 /IDPUTABLE6 OFFSET=FRONTFASTDAC
15-072-22:04:22 /IDPLOAD VALUE=0x60
15-072-22:05:07 /IDPUTABLE6 OFFSET=REARFASTDAC
15-072-22:05:17 /IDPLOAD VALUE=0x60
- Again 2015 March 17 D6 front fast threshold was increased:
15-076-20:44:01 /IDPUTABLE6 OFFSET=FRONTFASTDAC
15-076-20:44:14 /IDPLOAD VALUE=0x70
D6 front slow LLD threshold history
| post 2014 anneal | 0x0C (after segmentation)
|
| 2015 Jan 26 21:57:13 UTC | 0x30 (was 0x0C)
|
| 2015 Jan 27 21:37:03 UTC | 0x0C (was 0x30)
|
D6 front fast LLD threshold history
| post 2014 anneal | 0x22 (after segmentation)
|
| 2015-Jan-30 00:20:17 | 0x30 (was 0x22)
|
| 2015-Feb-27 21:41:44 | 0x40 (was 0x30)
|
| 2015-Mar-09 01:27:07 | 0x50 (was 0x40)
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| 2015-Mar-13 22:04:22 | 0x60 (was 0x50)
|
| 2015-Mar-17 20:44:14 | 0x70 (was 0x60)
|
D6 rear slow LLD threshold history
| post 2014 anneal | 0x30 (after segmentation)
|
D6 rear fast LLD threshold history
| post 2014 anneal | 0x45 (after segmentation)
|
| 2015-Jan-08 17:45:18 | 0x50 (was 0x45)
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| 2015-Jan-08 17:45:18 | 0x50 (was 0x45)
|
| 2015-Mar-17 22:05:17 | 0x60 (was 0x50)
|
D6 HV history
| post 2014 anneal | 4510 V (unsegmented)
|
| 2014-Aug-14 03:40 UTC | 4926 V (was 4510 V) (segmented)
|
