Tohban Report 2014-05-07

Tohban Reports
Start Date:	30 Apr 2014
End Date:	7 May 2014
Tohban:	Albert Shih (Vice Tohban: Brian Dennis)
Tohban email:	ayshih@ssl.berkeley.edu
Next Tohban:	Juan Carlos Martinez-Oliveros (Vice Tohban: Albert Shih)
List all reports

Solar Activity

Solar activity increased over the week, culminating in two M-class flares on 2014 May 6, one of which was observed well by RHESSI. The M-class flares came from active regions at the west limb.

How many GOES flares occurred?

 Flares above B, C, M, X class were     12    35     2     0

And how many of these are listed in the RHESSI flare list?

 Flares above B, C, M, X class were      4    20     2     0

And how many had EXCELLENT coverage?

 Flares above B, C, M, X class were      1     8     1     0

There were RHESSI flares/GOES flares 265 / 49 over the time range 30-Apr-14 07-May-14

Memory Management

The SSR fill level reached a maximum of 28% during the week, with the SSR not being completely emptied after a full set of passes. The decimation mode was changed on 2014 May 1 from active/vigorous to normal/vigorous.

Spacecraft Status

The spacecraft once again experienced spin-rate anomalies due to the orientation of the magnetic field that caused the ACS to switch to idle mode. The first time this week was noticed on a Santiago pass on May 2, and the spacecraft was commanded to precession mode. When next observed, the spacecraft had re-entered idle mode. Prior to commanding it to precession mode again, a spin-up was performed on May 3.

Data Gaps

There were no data gaps, but there have been some spikes in the data, similar to those noted in last week's tohban report. In particular, the C-class flare on 2014 Apr 30 at ~0125 UT not only has visible spikes, but also the full-Sun quicklook image shows two sources, which suggests a problem with the aspect solution. These spikes appear to be correlated with potentially noisy downlinks from Wallops, but historically noisy downlinks manifest as dropouts rather than spikes. Furthermore, in this case, the data was replayed at Santiago. It is still an open question why there are spikes in the data and whether they are "real" in any way (as opposed to a data-processing issue).

Detector issues

Nothing new.

Commands sent

Nothing beyond what is already discussed above.

Other notes

Brian Dennis was an excellent vice tohban!

Decimation	Normal/Vigorous
HLAT Decimation	Rear decimation weight 6, no front decimation
Night time data (fronts)	+/- 4 minutes
Night time data (rears)	+/- 4 minutes
Require extra passes?	No
Requirement for moving pointer?	No
Attenuator operation	Normal
Detector problems?	4, 8, 9