28 May 1995 L. Acton SXT CHIEF OBSERVER REPORT AND TABLE PLAN SXT TABLE PLAN FOR WEEK 22 (28-MAY-95 to 3-JUN-95) Solar activity has returned to beteewn A and B level. This will be a good week for the filament watch campaign. Also, It will be good for quiet sun studies. This plan will be modified if the solar activity level changes. Nariaki Nitta will take over as SXT Chief Observer this week. The observing objectives of this plan are: - Take advantage of days with 5 KSC passes for quiet corona studies. - Dark Calibration on TUESDAY. - Filament campaign. - Continuation of terminator-offpointing campaign. The SXT Table Plan for the week is as follows. PLEASE NOTE THAT THE NAME PART OF THE TABLE ID MAY CHANGE IF SOLAR CONDITIONS CHANGE. THE TABLE ID GIVEN IN THE FAX IS THE ID TO CHECK AGAINST THE UPLOAD FILE. We are entering the time when the date in UT does not agree with the date in JST. The date in the table ID is the UT date. KSC Time (start) in JST Pass Table ID Comments _____________(= UT + 9 hrs)______#_______________________________ Monday ****** No Table upload planned at this time. ******** Tuesday 30-MAY-95 14:09 5 950530 P5 ARS1 DKCAL Wednesday 31-MAY-95 07:38 1 950530 P1 ARS0 QT CORONA 31-MAY-95 14:29 5 950531 P5 ARS1 STD+LONG Thursday 1-JUN-95 06:15 1 950531 P1 ARS0 QT CORONA 1-JUN-95 13:06 5 950601 P5 ARS1 STD+LONG Friday 2-JUN-95 13:26 1 950602 P5 ARS0 FILAMENT Saturday 3-JUN-95 10:19 4 940603 P4 ARS1 STD+LONG Sunday ************* KSC HOLIDAY *************************** Terminator-Offpointing: The terminator-offpointing program will continue this week. The SSOC tohbans will be required to manually insert the off-point OGs for the terminators in the OP tables. The SSOC tohbans please fax the preliminary OP list to D-tou when it contains a terminator so that the Chief Observer can suggest the offpoints. Some new offpoint OG's will need to be prepared after the Chief Observer has decided what is needed. SXT CHIEF OBSERVER'S REPORT for Weeks 20 and 21: 14-MAY-95 to 27-MAY-95 This two week period included the SERTS rocket campaign wich was quite succesful as indicated in the following notice copied from the SERTS WWW homepage. SXT data for the SERTS orbit has been reduced and place online for the SERTS experiments -- although no acknowledgement has been received. May 25, 1995 STATUS The flight EUV film has been developed and shows beautiful imaged spectra at both pointing positions for a range of exposure times. Quick visual inspection indicates that spatial and spectral focus were excellent. The He II 303.78A and Si XI 303.32A lines are easily separated, for example. At the first pointing position, the limb appears sharp in He II 304A, and contrast between the general quiet sun and the northern polar coronal hole is clearly seen at that wavelength. Active region AR7870 is also well placed in these frames, showing considerable EUV structure which again demonstrates good optical focus. The second pointing position aimed for high resolution spectra of AR7870, and many lines appear throughout the full bandpass in these frames. In fact, one very pleasant surprise is the number of lines appearing between 235 and 300A. The new multilayer coated grating was designed to enhance efficiency in the range 170 - 220A; we were prepared to sacrifice some performance outside that band. But quite a few 'out of band' lines appear, even so. Next comes film microdensitometry, and quantitative analysis. Then the fun really begins! Following the SERTS campaign SXT observed the complex of activity around AR 7869 and AR 7870, plus several quiet sun studies. IAU Colloquium 153 took place during week 21 so mostly the SXT was left to do its own thing under ARS1. SXT INSTRUMENT STATUS The SXT instrument continues to operate without any problems. New software has been written to permit better understanding of what terminator images are most needed. Nitta san will now use these new tools to specify new offpoint OG commands and to guide the terminator program. We have several serious gaps in the terminator image data base which need to be filled. Now that the sun is so quiet ARS1 is chasing dark spikes again. These data are not useless because they tend to go to the same dark spike in the north east and can be summed together for quiet coronal studies. It is possible that the patrol image can be better optimized -- another job for the SXT Chief Observer. The other option is to use ARS2, ARS0 or ART during times when the Sun is very quiet. KSC tobans should continue to dump a patrol image each time an SXT table is loaded to provide a data base for study of ARS target finding. QUIET SUN OBSERVING A special table designed to optimize use of SXT observing time was run for 4 orbits on 28-May. More than 1 hour of PFI observing was accumulated through the AlMg filter and over a half hour in the Al.1 filter -- intermixed with a dark frame about every 5th cycle through the table. This program produces excellent data for quiet corona studies but can only safely be run when the x-ray level is at Low-B or A levels because the shutter remains open essentially all of the time. CALIBRATION STATUS Because of other demands on Morrison san's time the improvement in SXT dark frame correction has not yet been completed. It is planned to use dark frames formed by averaging as many dark images as possible to improve statistics for work with faint signals. An orbit phase correction will also be applied. CAMPAIGNS I forget. Nitta san will tell you what campaigns are coming up.