Report from ISAS 19 September - 2 October, 1994 James R. Lemen SUMMARY During the past week SXT has been participating in two observing campaigns. One was a Bright Point campaign organized by Karen Harvey with participation by Kitt Peak, Big Bear, and Mees Observatories. The campaign last a week but was hampered by poor weather conditions. The next campaign will likely be scheduled in late November this year. The other campaign was organized by Brigitte Schmieder and her colleagues at Meudon, entitled "Chromospheric Ejections and Coronal Loops." The overall solar activity level was quite low duing this period. SXT operations went very well and a new SXT halt procedure was tested. OPERATIONS This week's operation went very well. Two campaigns were conducted, but since the ground observers of one campaign were in Europe and the other in southwest U.S., there was not much conflict. Two SXT tables were loaded each day: one to support the bright point campaign and the other to support the chromospheric ejections campaign. The BP SXT table used a 2.6 arc min (64 pixel) NS by 7.9 arc min (3*64 pixel) EW field of view with no ARS tracking. The chromospheric campaign made use of the standard table with ARS2 to stay on a selected active region. In the shuffle of Chief Observers, we overlooked the dark calibration last week, so we have a two-week gap in our dark calibration database. With the bright point campaign completed, we will resume the acquisition of terminator images at the off-pointed positions used during the Spartan campaign. The main emphasis will be to acquire AlMg and Mg3 filter data, since most of the thin off-point positions have data for thin Al. SOLAR ACTIVITY Solar activity continued at a very low level throughout the past two weeks, in the mid-A to mid-B range for most of the period. hovering around the A1 level for most of the period. A large coronal hole has rotated onto the disk in the north and this was the target region for the bright point study for much of the week. The Chromospheric campaign started tracking AR 7782 and 7781 until it reached the west limb and then switched to a new southern region, AR7783. AR7783 is now at near sun center and a new region, AR7784 has appeared in the south east. Both of these regions appear to fairly simple magnetic configurations and there are almost no filaments at the present time. PERSONNEL Marilyn Bruner has returned to California. Jean-Pierre Wuelser is traveling in Japan and will return to Hawaii on 3 Oct 94. Hugh Hudson and James Lemen arrived at the beginning of last week and have jointly assumed SXT Chief Observer duties. David Alexander arrives on 3 Oct. Sam Freeland has been making good progress in getting the archive reformatting caught up (there is only a two-week backlog now). Josef Khan (MSSL) has been visiting for the past few weeks. SCIENCE Jean-Pierre Wuelser made very good progress on two important SXT subjects. The first is the alignment of SXT and HXA. He had done an analysis of this more than a year ago and it was time to extend this work to the current epoch. This has been done with reference to the full-Sun X-ray limb fits that are not routinely made by the reformatting software. A draft of a memo has been circulated. Also, Jean-Pierre has reviewed the Mercury transit data. This data set has proven to be an extremely valuable means to evaluate the SXT roll angle (with respect to the spacecraft) and also the SXT pixel size. The analysis software currently assumes the prelaunch calibration values for both of these quantities. Jean-Pierre's work recommends small adjustments to the prelaunch values and the software will be updated in the near future. Josef Khan has assembled an impressive list of SXT-observed over- the-limb flares working primarily with Hudson, Harra, and Sterling. Among other topics, they hope to compare the signature of BCS line profiles and the BCS-derived temperatures with the observed geometry of the SXT flare images.