7 December 1998 Mark Weber SXT CHIEF OBSERVER'S REPORT AND TABLE PLAN CHIEF OBSERVER'S REPORT for Week 50 7-Dec-98 to 13-Dec-98 GENERAL Yohkoh and SXT continued to perform without problems this week. Solar activity was noticeably (but not greatly) higher than the previous week, with several LDEs in the low- to mid-C range. The GOES background also rallied to C1 level by the middle of the week. There were no (0) M-class flares. SXT TECHNICAL The SXT instrument is functioning nominally. SXT SCIENCE For Web material see Current Week: http://www.solar.isas.ac.jp/sxt_co/SXTweekly.html Current Week: http://www.solar.isas.ac.jp/sxt_co/981213.html Index: http://www.solar.isas.ac.jp/sxt_co/index.html This week's Science Nugget looks at a high latitude large arcade which runs north-south. CAMPAIGNS There were no formal joint observing campaigns this week. The TRACE planner responded to a query from the SXT CO-- they will start sending emails of their observing schedule once again. SXT was able to follow AR 8406 in conjunction with TRACE and the VLA for a few hours of flare study on Friday. PERSONNEL Nothing to report. SEMINARS The seminars this week were given by K. Shibasaki, on the role of ballooning instabilities in filament evolution, and by S. Kubo, on the solar rotation. Discussion was lively! 11 December 1998 M. Weber SXT TABLE PLAN, WEEK 51 (14-Dec-98 --- 20-Dec-98) We know of no particular plans for coordinated observations, but will keep our eyes on TRACE and CDS as usual. TRACE has promised to start sending their operation plans again. ________________________________#_______________________________ JST Day UT Start Time Pass Table ID Monday 14-DEC-98 10:03 3 981214 P3 ARS1 DARKCAL Tuesday 15-DEC-98 10:20 3 981215 P3 ARS1 STD Wednesday 16-DEC-98 08:53 3 981216 P3 ARS1 STD+DIFF " 16-DEC-98 12:20 5 981216 P5 ARS1 STD Thursday 17-DEC-98 10:53 4 981217 P4 ARS1 STD Friday *** Yohkoh Holiday *** Saturday 19-DEC-98 07:59 3 981219 P3 ARS1 STD Continuing requests: KSC & SSOC Tohbans: If any KSC passes are likely to be cancelled (for example due to a typhoon) or an SXT table cannot be uploaded for some reason, please telephone and e-mail the Chief Observer immediately. (sxt_co@isass0.solar.isas.ac.jp, copy to sxt_st@flare2.solar.isas.ac.jp). SSOC Tohban: On the weekly visible diagram, please mark the official five passes first and then cross out those passes that will be given to other satellites. That way we can keep the numbering straight in the Yohkoh software system. SSOC Tohban: SXT operations do not currently include terminator off- pointing. It is unnecessary this week to ask the SXT Chief Observer for terminator off-pointing information. KSC Tohbans: In general flare mode supersedes table upload, ie if a flare is in progress please do not upload a new table, and contact the chief observer. Normally it is OK to go ahead with the planned table without change on the next pass, if it is available. Chief observers should keep an eye on this.