26 May 1996
                                                         Nariaki Nitta
                                                     
                                                      
                SXT CHIEF OBSERVER REPORT AND TABLE PLAN

SXT CHIEF OBSERVER'S REPORT for Week 21:   20-MAY-96 to 26-MAY-96

SOLAR ACTIVITY

After AR 7962 disappeared into the other side of the Sun, solar activity has
been extremely low, not even hitting the GOES A level.  The high latitude 
regions that were reported as those from solar cycle 23 have not shown much 
activity.  A quiet corona observing plan would have been quite successful.


SXT INSTRUMENT STATUS 

On a first image from Monday morning, we saw a vertical streak from where 
AR 7962 was sitting.  Its intensity did not seem to depend on exposure
durations.  It is likely to have been caused by many long exposures in 
coordination with SoHO.  It has decayed during the week, and now it is hard
to see.  Otherwise we had no significant SXT errors last week (two bit map 
errors on Monday).  SXT has continued to be operational.


CAMPAIGNS

We coordinated with Markus Aschwanden on Friday and Saturday, who was
observing the north polar and west limb regions with VLA, KPNO, OVRO
and SoHO.  The last run is scheduled for Monday morning.


SEMINARS

On Thursday, 23 May, we had a regular Yohkoh seminar.  Two ISAS guests were
featured.  The speakers and titles were
  J. Wang: "Magnetic Flux Emergence and Cancellation" and
  F. Farnik: "Study of the Oct. 3, 1993 Flare."



                       SXT TABLE PLAN FOR WEEK 22
                        (27-May-96 to 2-Jun-96)


Most of this week will be devoted to Karen Harvey's X-ray bright point campaign. 
Until we have more confidence in safety of the CCD, we will go back to a 
standard table at pass 4.  This means that we will have two table uploads every
day.  The dark calibration table will be loaded on Monday, and the weekly 
diffuser images included as part of a standard table on Friday. 

The provisional SXT Table Plan for the week is as follows:

    KSC Time (start) in JST     Pass          Table ID        
_____________(= UT + 9 hrs)______#_______________________________
 
Monday	    27-MAY-96 03:50      1         960526 P1 ARS0 STD VLA
Monday	    27-MAY-96 09:00      4         960526 P4 ARS1 DKCAL
Tuesday     28-MAY-96 02:30      1         960527 P1 ARS0 STD XBP
Tuesday     28-MAY-96 07:35      4         960527 P4 ARS1 STD+LONG
Wednesday   29-MAY-96 02:50      1         960528 P1 ARS0 STD XBP      
Wednesday   29-MAY-96 07:55      4         960528 P4 ARS1 STD+LONG
Thursday    30-MAY-96 01:25      1         960529 P1 ARS0 STD XBP
Thursday    30-MAY-96 06:35      4         960529 P4 ARS1 STD+LONG
Friday      31-MAY-96 01:45      1         960530 P1 ARS0 STD XBP
Friday      31-MAY-96 06:55      4         960530 P4 ARS1 STD+DIFFU
Saturday     1-JUN-96 00:20      1         960531 P1 ARS0 STD XBP
Saturday     1-JUN-96 05:30      4         960531 P4 ARS1 STD+LONG


*** Please note that this table plan may change ***


Dumping Patrol images:
   We request that KSC tohban continue to dump a patrol image each time an
SXT table is loaded to facilitate the study of optimizing ARS parameters
for an awfully quiet period. 

  SSOC TOHBAN, please fax the preliminary OP list to D-tou when it contains
a terminator so that the Chief Observer can suggest which OG's to use. 

  PREPARATION OF OGs: New OGs were made last week, but no terminator images
have been taken since then.  We may change OGs this again this week.