Tohban Report 2009-11-04

From RHESSI Wiki

Jump to: navigation, search

Tohban Reports
Start Date: 28 Oct 2009
End Date: 04 Nov 2009
Tohban: Pascal Saint-Hilaire
Tohban email:
Next Tohban: Neus Agueda
List all reports


Solar Activity

After a flurry of activity last week, the GOES level went back to its lowest state as the AR went beyond the limb.

How many GOES flares occurred?

 Flares above B, C, M, X class were     31     7     0     0

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

 Flares above B, C, M, X class were     19     6     0     0

And how many had EXCELLENT coverage?

 Flares above B, C, M, X class were     10     5     0     0

There were RHESSI flares/GOES flares 75 / 38 over the time range 27-Oct-09 03-Nov-09

Memory Management

Decimation was normal/active for the week. Front segment events are not turned off during eclipses. SSR was did not go above 25% the whole week. But...this morning, SSR jumped to 97.64%!!!

The reason is that a Wallops pass got corrupted, and needed to be re-played. The data were about to be written over, and when Jeremy put the Read pointer right after the Write pointer, the SSR fill level registered almost 100% full. This state (which has happened before) lasted for about 6 minutes, but finished *after* the last status page update, leading to the 97.64% reading until the next set of passes.

Data Gaps

We seem to have had a 2-hour VC3 (only) data gap on 2009/11/02:

DATA GAPS FOR 2009/11/02 TIME RANGE: 2009-11-02T00:00:00.000 -- 2009-11-03T00:00:00.000 NO GAPS IN APP_ID = 1 (VC1-SOH) NO GAPS IN APP_ID = 154 (VC1-PMTRAS) GAPS IN APP_ID = 102 (VC3-MONITOR RATES) WITH PACKET RATE LT 30 N_GAPS 1 GAP START TIME GAP END TIME GAP (SEC) 2009-11-02T08:50:00.000 -- 2009-11-02T10:55:00.000 7500.0000

This is the file that needed to be retransmitted, and should now be in the queue.


1) The near 100% fill level created by the situation described above caused a heavy decimation level to kick in (15 in 16 counts thrown out), and seemed to have caused the thin attenuator to kick in. We are not quite sure why. Part of the full memory emergency procedure? High rates due to SAA? Jim will try to dig the flight software information pertaining to that. In the future, it has been decided that Operations should consult with the tohban before replaying data, if that would cause the SSR level to be more than 80% full (corresponding to the level where heavy decimation kicks in).

2) Brian Dennis has reported that detector 7 showed a large amount of pulse-pileup during the 2002 July 23 flare (during times with attenuator state 3), much stronger than in the other detectors.

Personal tools