Tohban Report 2016-01-13
| Tohban Reports | |
|---|---|
| Start Date: | 6 Jan 2016 |
| End Date: | 13 Jan 2016 |
| Tohban: | Juan C. Martinez Oliveros |
| Tohban email: | oliveros@ssl.berkeley.edu |
| Next Tohban: | Jim McTiernan |
| List all reports | |
Solar Activity
Solar activity was low this week, with a couple of C-class flares during the week. There are currently 6 ARs on the disk with the probability of some C class flares in the following days. Three of the active regions will rotate out of the disk in following days.
How many GOES flares occurred?
Flares above B, C, M, X class were 23 2 0 0
And how many of these are listed in the RHESSI flare list?
Flares above B, C, M, X class were 12 2 0 0
And how many had EXCELLENT coverage?
Flares above B, C, M, X class were 8 2 0 0
There were RHESSI flares/GOES flares 42 / 25 over the time range 06-Jan-16 13-Jan-16
Memory Management
The SSR fill level reached a maximum of 50% and a minimum of about 10% during the week.
Spacecraft Status
The cold plate 1 and 2 are at about 138.2 K and 136.8 K respectively.
Data Gaps
No data gaps this week.
Detector issues
Detector 4: a experiment was performed on January 8, consisting in lowering the voltage of the detector from 500V to 200V, start taking events, then stop taking events and ramp back to 500V the detector.
2016-008-01:31:37 /IHVDAC DETECTOR=4, VOLTAGE=10 ; 200 V 2016-008-01:32:07 /ITMON VALUE=AFE3 ; turn on G4 events
2016-008-01:35:37 /ITMOFF VALUE=DIB4 ; turn off G4 events 2016-008-01:35:46 /IHVDAC DETECTOR=4, VOLTAGE=28 ; return to 500 V
After analysis of the spectrum it seems like the number of counts measured are comparable to the other detectors. Because the experiment was made during a night period, it was not possible to have simultaneous observations with all the detector. For comparison, I used the last minute before stop taking events in all detectors.
Detector 6: As was suggested during the last ops meeting, the slow front threshold of the detector was changed from 0x30 to 0x80 (~25keV). No decrease in the slow counts was observed.
2016-008-01:32:23 /IDPUTABLE6 OFFSET=FRONTSLOWDAC 2016-008-01:32:32 /IDPLOAD VALUE=0x80 ; was 0x30
Following the behavior of the detector, it was notice that the observed feature (bump) started to drift in the direction of the high energies. Because of this, the only solution to lower the slow counts seems to be a drop of the detector’s HV
Detectors 1,5,7: The detectors seems to be working fine, but their lifetime is degrading.
Other notes
The thin attenuator came in on Jan 12, 09:06 UTC and did not come out. The deadtime threshold for that attenuator to come out was 15.29 % and it seems like the background has come up to about 17%. For this reasons the the attenuator thresholds was increased to reflect the increased background dead-time of about 17.6 % This commanding was done at 2016-013-00:57 UTC. The thin attenuator came out a few seconds later.
Spacecraft Management
| Decimation | Active/Vigorous |
| Night time data (fronts) | +- 4 minutes |
| Night time data (rears) | +- 4 minutes |
| Require extra passes? | No |
| Requirement for moving pointer? | No |
| Attenuator operation | See above |
| Thin Att. in | 22.74% |
| Thin Att. out | 19.21% |
| Thick Att. in | 24.70% |
| Thick Att. out | 18.43% |