April 28, 2000 B. N. Handy CHIEF OBSERVER'S REPORT for Week 18 24-April-00 through 30-April-00 GENERAL Yohkoh supported JOP120 (Sigmoids) and an unofficial effort to look at trans-equatorial loops, but overall a quiet week. Flare activity remained low, with the background GOES level at sub B-class. SXT TECHNICAL SXT functioned properly. There were no apparent problems this week. For Web material see Current Week: http://isass1.solar.isas.ac.jp/sxt_co/000428.html Index: http://isass1.solar.isas.ac.jp/sxt_co/index.html This week's nugget correlates the solar cycle to the degradation in altitude of the Yohkoh orbit. We compare the long-lived Yohkoh orbit to that of ASCA. CAMPAIGNS Next week will include JOP 83 (Loop Oscillations and Heating in active regions) and JOP 17 (Prominence studies). Two target of opportunity JOPS that may see use are trans-equatorial loops and Sigmoids. For SXT plans, see: http://isass1.solar.isas.ac.jp/sxt_co/sxt_future.html For SXT completed campaigns, see: http://isass1.solar.isas.ac.jp/sxt_co/sxt_catalog.html PERSONNEL No changes. SEMINARS K. Shibasaki: "Supra-arcade Downflows" This week: no seminar planned. SXT TABLE PLAN, WEEK 18 (30-Apr-00 - 06-May-00) JOP 83 (AR Loop oscillations and Heating), JOP 17 (Prominence Studies) ________________________________#_______________________________ JST Day UT Start Time Pass Table ID Monday PM 01-MAY-00 10:15 4 000501 P3 ARS1 DKCAL Tuesday PM 02-MAY-00 07:00 2 000502 P2 ARS1 DIF Tuesday PM 02-MAY-00 10:24 4 000502 P4 ARS1 JOP 83 Wednesday PM 03-MAY-00 07:09 2 000503 P2 ARS2 JOP 83 Thursday PM 04-MAY-00 07:14 2 000504 P2 ARS1 JOP 83 Friday PM 05-MAY-00 07:19 2 000505 P2 ARS1 JOP 83 Saturday PM 06-MAY-00 08:13 4 000506 P4 ARS1 STD Continuing requests: KSC & SSOC Tohbans: If any KSC passes are likely to be cancelled (for example due to heavy snowfall) 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). KSC Tohbans: In general flare mode supersedes table upload, i.e. 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.