Detector 9
From RHESSI Wiki
(Difference between revisions)
(→D9 HV history) |
|||
| Line 61: | Line 61: | ||
15-084-19:28:33 /ihvdac detector=9, voltage=156 | 15-084-19:28:33 /ihvdac detector=9, voltage=156 | ||
15-084-21:05:17 /ihvdac detector=9, voltage=136 (2622 V) | 15-084-21:05:17 /ihvdac detector=9, voltage=136 (2622 V) | ||
| + | |||
| + | * As of early April, detector 9 rear segment is now essentially non functional. Rear fast rates have increased to the point where livetime dropped to zero, and the fast threshold is already turned all the way up so we have no way to control those rates. The front segment appears to be operating normally, though its fast AND slow rates are high (but not worringly so). | ||
| + | |||
| + | * 2015 April 7: To deal with slightly reduced livetime in the FRONT segment, we changed the front fast threshold. This does NOT seem to have had an effect!! | ||
| + | 15-097-19:58:06 /IDPUTABLE9 OFFSET=FRONTFASTDAC | ||
| + | 15-097-19:58:14 /IDPLOAD VALUE=0x30 ; was 0x22 | ||
| + | |||
===D9 front slow LLD threshold history=== | ===D9 front slow LLD threshold history=== | ||
| Line 72: | Line 79: | ||
|- | |- | ||
| post 2014 anneal || 0x22 | | post 2014 anneal || 0x22 | ||
| + | |- | ||
| + | | 2015-Apr-07 19:58 || 0x30 (was 0x22) | ||
|- | |- | ||
|} | |} | ||
Revision as of 01:10, 9 April 2015
This page contains information about changes/issues for RHESSI detector 9 after the 2014 anneal. Detector updates from 2012-mid 2014 can be found here: Detector 9 anneal 2012
Contents |
Notes
Detector 9 is SEGMENTED after the 2014 anneal!
- 2014 August 20: Due to sporadic noise in D9, the HV was dropped by 20 counts (now at 3600V). Commanding was at 20:57 UTC. This successfully quieted the noise. The noise was mainly fast counts, which cut drastically into the livetime.
- 2014 October 8: This detector has started to show some periodical spikes during last couple of days. Still is not clear what is their origin. It seems to be periodic with the orbit. So far no action taken.
- 2014 Oct 31: Elevated noise during the period of Oct 31 - Nov 2. The onset, as well as the abatement was sudden. No commanding was done and the noise returned to regular levels.
- On 2015 Jan 8, the rear fast threshold was raised since fast counts were eating up a lot of livetime.
15-008-17:45:50 /IDPUTABLE9 OFFSET=REARFASTDAC 15-008-17:46:04 /IDPULOAD VALUE=0x50 ;(was 0x45)
- Rear fast counts are high again, so we raised the rear fast threshold by 16 steps, in two sets of 8, on the BGS pass starting at ~3:30 PST. The new value is 0x60 (was 0x50). Fast rates as eyeballed from the realtime data were approx 58,000 (pre-adjustment), 12,000 (after 8 steps up), and 1600 (after 16 steps up). Livetime percentages were approx 60%, 90%, and 98%, respectively.
15-021-23:33:58 /idpudumptabl table=dibtbl9 15-021-23:34:03 /idputable9 offset=rearfastdac 15-021-23:34:34 /idpuload value=0x58
15-021-23:36:47 /idputable9 offset=rearfastdac 15-021-23:36:55 /idpuload value=0x60
- The rear fast threshold was raised again for the same reasons as the last two adjustments. The threshold was raised in two jumps of hex 8 each.
15-057-18:43:13 /IDPUTABLE9 OFFSET=rearfastDAC 15-057-18:45:14 /IDPLOAD VALUE=0x68
15-057-20:21:52 /IDPUTABLE9 OFFSET=REARFASTDAC 15-057-20:22:09 /IDPLOAD VALUE=0x70
- Rear fast threshold changed again, usual reason.
15-064-19:39:50 /IDPUTABLE9 OFFSET=REARFASTDAC 15-064-19:40:12 /IDPLOAD VALUE=0x80 ; was 0x70
- And again, on March 11, 2015.
2015-070-22:46:04 /IDPUTABLE9 OFFSET=REARFASTDAC 2015-070-22:46:19 /IDPLOAD VALUE=0x90
- On March 13, 2015 the rear fast threshold was changed again
15-072-22:06:18 /IDPUTABLE9 OFFSET=REARFASTDAC 15-072-22:06:31 /IDPLOAD VALUE=0xA0
- And then again, on March 16, 2015.
15-075-19:24:13 /IDPUTABLE9 OFFSET=REARFASTDAC 15-075-19:24:28 /IDPLOAD VALUE=0xB0
- And then again, on March 18, 2015.
15-077-TBD /IDPUTABLE9 OFFSET=REARFASTDAC 15-077-TBD /IDPLOAD VALUE=0xC0
- And again, on March 25, 2015.
15-084-21:07:00 /IDPUTABLE9 OFFSET=REARFASTDAC 15-084-21:07:14 /IDPLOAD VALUE=0xFF
- In addition we change the HV on March 25, 2015:
15-084-19:26:07 /ihvdac detector=9, voltage=176 15-084-19:27:17 /ihvdac detector=9, voltage=166 15-084-19:28:33 /ihvdac detector=9, voltage=156 15-084-21:05:17 /ihvdac detector=9, voltage=136 (2622 V)
- As of early April, detector 9 rear segment is now essentially non functional. Rear fast rates have increased to the point where livetime dropped to zero, and the fast threshold is already turned all the way up so we have no way to control those rates. The front segment appears to be operating normally, though its fast AND slow rates are high (but not worringly so).
- 2015 April 7: To deal with slightly reduced livetime in the FRONT segment, we changed the front fast threshold. This does NOT seem to have had an effect!!
15-097-19:58:06 /IDPUTABLE9 OFFSET=FRONTFASTDAC 15-097-19:58:14 /IDPLOAD VALUE=0x30 ; was 0x22
D9 front slow LLD threshold history
| post 2014 anneal | 0x0C |
D9 front fast LLD threshold history
| post 2014 anneal | 0x22 |
| 2015-Apr-07 19:58 | 0x30 (was 0x22) |
D9 rear slow LLD threshold history
| post 2014 anneal | 0x30 |
D9 rear fast LLD threshold history
| post 2014 anneal | 0x45 |
| 2015-Jan-08 17:46:04 | 0x50 (was 0x45) |
| 2015-Jan-22 23:34:34 | 0x58 (was 0x50) |
| 2015-Jan-22 23:36:55 | 0x60 (was 0x58) |
| 2015-Feb-27 18:45:14 | 0x68 (was 0x60) |
| 2015-Feb-27 20:22:09 | 0x70 (was 0x68) |
| 2015-Mar-05 19:40:12 | 0x80 (was 0x70) |
| 2015-Mar-11 22:46:19 | 0x90 (was 0x80) |
| 2015-Mar-13 22:06:31 | 0xA0 (was 0x90) |
| 2015-Mar-16 19:24:28 | 0xB0 (was 0xA0) |
| 2015-Mar-18 21:52:57 | 0xC0 (was 0xB0) |
| 2015-Mar-18 23:32:15 | 0xD0 (was 0xC0) |
| 2015-Mar-25 21:07:00 | 0xFF (was 0xD0) |
D9 HV history
| post 2014 anneal | 3995 V |
| 2014-Aug-20 | 3603V (was 3995V) |
| 2015-Mar-25 | 2622V (was 3603V) |
