SXT Status Report
                       7 July 1997 to 21 July 1997
                             (Weeks 28,29)
                          H. Hudson, S. Savy 


SUMMARY

SXT continued to operate well. Solar activity was low, with only one
C-class flare observed during the interval.

SOLAR ACTIVITY

There were four numbered NOAA regions during the interval, maximum
sunspot area 30 millionths. Two listed GOES events. Pretty dull, but
small new-cycle regions keep popping off.

However: the quite remarkable streamer bottom observed on June 21 (E limb) and
July 5 (W limb) returned to the E limb! Woe to any filament eruption
search that homes in on this one. As described last report, this has
an exceptionally well-defined cavity, bulging outwards in a manner 
reminiscent of the celebrated 21 Feb 1992 flare event.  Plus, an X-ray
bright region surrounding the filament. This structure seems to be bringing
us some new facts about filaments, too bad it did not happen prior to the
Aussois meeting.

SXT INSTRUMENT STATUS

SXT continues to perform well technically.  

The network connection from ISAS to the US (or to the Japanese commercial 
network) remains very bad. There are no rumors of improvements. On "Ocean
Day", a national holiday in Japan, it was possible to see Web pages generated
at GSFC.

SXT CALIBRATION ACTIVITIES

The bakeout planned for this interval was postponed for two weeks when
it was noted that the KSC passes are currently at night, making confirmation
of the power commands difficult.

PASS CONFLICTS

Week 28: 3 passes cancelled for HALCA
Week 29: 5 passes cancelled for HALCA 

CAMPAIGNS

There were coordinated observations with CDS during week 28, looking
at AR loops. The data set looks good and will perhaps be one of the
featured items at the 2nd SOHO/Yohkoh CDAW, to take place at Medoc
(Paris) in October.

For Yohkoh target planning, the SXT weekly observing plan is available on
the Web at
        http://www.space.lockheed.com/SXT/html2/First_Light.html
or with
        "finger campaign@isass0.solar.isas.ac.jp | more"        .

See http://sohowww.nascom.nasa.gov/operations/targets/today"
for SoHO target planning.

VISITORS AND PERSONNEL

No personnel changes among SXT personnel; Lee McDonald (BCS) returned
to Japan and Alphonse Sterling (BCS) left for a bit. 

SEMINARS

July 10:

T. Yokoyama (NAO): "Two-dimensional MHD simulation of chromospheric
  evaporation driven by magnetic reconnection"
M. Ohyama (NAO): "X-ray plasma ejections associated with impulsive
  solar flares"

July 17:

M. Shimojo (GUAS), "Physical parameters of solar X-Ray jets --
  observation and simulation"
S. Yashiro (NAOJ), "Evolution of coronal active regions observed with
  the Yohkoh soft X-ray telescope"


TOHBANS

Tohbans for Week 28:

    SSOC :  Sawa, Nagata
    KSC  :  Yashiro, Kano 
    SXT_CO: Hudson 
    SXT_SW: -

Tohbans for Week 29:

    SSOC :  Yoshida, McDonald 
    KSC  :  Kano, Torii 
    SXT_CO: Hudson 
    SXT_SW: -