RHESSI Tohban report, 12-nov-2002 to 18-nov-2002

Satoshi Masuda, masuda@ssl.berkeley.edu / masuda@stelab.nagoya-u.ac.jp


1. Solar Activity:

The solar activity was relatively high this week.  The GOES (1-8 A)
background level was almost always above the C1 level.  Six M-class events
and many C-class events occurred.  There was no X-class flare this week.

2. Coordinated observations:

None that we knew about.

3. Memory Management:

On 11 Nov (last Monday), the shutter mode was changed from A013 mode to 
A13 mode, corresponding to a relatively high solar activity. 
That mode lasted until ~ 18 UT on 15 Nov 2002 (Fri).

A013 -> A13   11-nov-2002  19:30:20
A13 -> A013   15-Nov-2002  18:06:07

4. Data Gaps:

There are two data gaps as shown below as of 19 UT on 18 November.

GAP START TIME              GAP END TIME                 GAP (SEC)
2002-11-12T19:20:00.000Z -- 2002-11-12T21:30:00.000Z      7800.000
2002-11-14T13:25:00.000Z -- 2002-11-14T16:40:00.000Z     11700.000


5. SSR management

In the third pass (19:44 UT - 19:55 UT) on November 15 (Fri), David
Smith's new decimation table was uploaded.  The major difference from
the older table is that the new scheme begins decimation at 30% SSR
fill level, rather than 50%.  The change is recognizable in the data as
the science header version number was incremented to 11.

New table: (Values are top decimated energy level/decimation depth)

               ____________Shutters____________
SSR level     open     thin      thick     both
                                (unused)
30-50          4/1      0/0        0/0     0/0                                
50-60          6/1      7/1        8/1     9/1 
60-70          6/2      7/2        8/2     9/2 
70-80          8/3      9/3       10/3    11/3 
80-90         10/5     11/5       12/5    13/5 
90-95         12/7     13/7       14/7    15/7 
95-99         15/15    15/15      15/15   15/15    
99+ events off.

Decimation depth N means N out of (N+1) events are deleted.

6. Special Operations. 

The following is quoted from Mark's report.

  On Wednesday, Nov 13, the iattflux resolution was changed from 0-100 
to 0-255. This will allow for more precise control of the shutter movements. 
In accordance, the shutter thresholds were changed to pull the thin shutter 
out when iattflux is below 0.8% and to pull the thick shutter out 
when iattflux is below 1.6%.

  The RHESSI FOT was conducting our third `hands-off weekend' Nov 16-17. 
The FOT will go to 5-day operations effective next week. 
Tohban must check data gaps carefully during weekend.


7. Tohbans

Week of 19-Nov to 25-Nov: Jim McTiernan (19-23), and David Smith (24-25)