June 26, 1999 Piet Martens CHIEF OBSERVER'S REPORT for Week 26 21-Jun-99 to 27-Jun-99 GENERAL Activity was very high, with numerous C flares, and four M flares. Most were in the series of Active Regions in the NE quadrant, and quite often flares took place in the target region for the first Max Millennium campaign. As of June 26 there were 21 Active Regions on the disk! SXT TECHNICAL No problems. The dark current has leveled off at 31.7 DN/s/pixel, up from 31.2 in May and previously. We returned to the streamer offset coordinates to get a terminator image in Al.1. The operations in support of SERTS were jeopardized by an SEU discovered on the first KSC pass (we had only 1, 4, and 5, and the rocket went between 4 and 5). The KSC tohbans were able to clear the error and load the special table properly on pass 4, so we began observations just in the nick of time. The SSOC tohbans had neglected to use "campaign mode" to protect the key data, but we got lucky and obtained 11 PFI images anyway. We thank the KSC tohbans for their swift and decisive actions, that saved the day. 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/990625.html Index: http://www.solar.isas.ac.jp/sxt_co/index.html This week's science nugget shows simultaneous and co-aligned SXT and TRACE data taken during the SERTS sounding rocket flight. CAMPAIGNS SXT supported the SERTS sounding rocket flight from White Sands Missile Range in New Mexico (USA), with a special observing program. The flight took place on 24-Jun-99 from 17:00 to 17:10 UT, and 5 spectra were obtained with the slit across the active regions in the NE quadrant. SXT took 2 series of 2X2 PFI's of the target region in 5 filters, and one darkcal PFI, as well as 2 FFI's. Other participants were CDS, EIT, and MDI on SOHO, and Kitt Peak, Sac Peak, and Big Bear in the US. SXT also participated in the second week of the First Max Millennium campaign, together with TRACE, SOHO, and 27 ground based observatories on 6 continents (all except Antarctica). SXT followed the brightest region on the disk in ARS1, which was also the target region for all of this week. For more information on campaigns, see: http://sec.noaa.gov/solcoord/solcoord.html For SXT plans, finger campaign@isass0.solar.isas.ac.jp. PERSONNEL Brian Handy arrived on Sunday. SEMINARS No SXT seminar this week. Piet Martens gave a seminar on NAOJ on "Moss as a Coronal Barometer", that fostered interest from Japanese students in analyzing TRACE data. **************** SXT TABLE PLAN, WEEK 27 (28-Jun-99 to 3-Jul-99) The Max Millennium flare campaign will continue until June 29. SXT will continue to follow the brightest region un the disk. ________________________________#_______________________________ JST Day UT Start Time Pass Table ID Monday 28-JUN-99 12:31 3 990628 P3 ARS1 STMAX01 Tuesday 29-JUN-99 09:21 2 990629 P2 ARS2 DASTAND Wednesday 30-JUN-99 09:35 2 990630 P2 ARS2 DISTAND Thursday 01-JUL-99 09:50 2 990701 P2 ARS0 STANDARD Friday 02-JUL-99 08:22 2 990702 P2 ARS2 STANDARD Saturday 03-JUL-99 10:19 3 990703 P3 ARS1 STANDARD "MAX01" stand for first Max Millennium campaign. As previously, the (*) in a table name means that the UT date and the JST date don't match. This plan is subject to change. 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, 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.