SXT Status Report 19 February - 11 March, 2001 (Weeks 8-10) N. Nitta, A. Takeda SOLAR ACTIVITY Activity in terms of flares has stayed low with only four flares above the M1 level. The GOES background level fluctuated between B3 and C1. Prominent non-polar coronal holes were seen first in the southern hemisphere and then in the northern hemisphere. Many eruptions were observed, whose appearances reminded us that they intrinsically had 3-d structures and trajectories. OBSERVING CAMPAIGNS We participated in three campaigns - the MEDOC quiet Sun campaign, JOP 137 (Time Variation and dynamics of active region loops II - unsolicited) and JOP 138 (Decimetric storms and Decametric type III bursts). In addition, we continued a target-of-opportunity (TOO) search for sigmoid structures, but could not find nice ones. Please see our webpages for more details about campaigns past and future: http://isass1.solar.isas.ac.jp/sxt_co/sxt_catalog.html http://isass1.solar.isas.ac.jp/sxt_co/sxt_future.html SXT INSTRUMENT STATUS AND CALIBRATION ACTIVITIES SXT continued to be in fine working order. There was an apparently SEU-induced error (on 1-Mar-2001) in combination with the on-board data processor, but it was cleared without delay with the usual procedures. After an extended Canopus eclipse period which ended on 21-Feb-2001, the spacecraft roll was re-adjusted. We updated the normal pointing on 1-Mar-2001. TELEMETRY DOWNLINKS Week Wallops Santiago Goldstone Canberra Madrid NASA Japan 08 32 1 9 7 0 49 32 09 31 1 3 6 0 41 31 10 25 0 0 8 0 33 23 Kagoshima should average 6*5+2 = 32 and the NASA target is 7*6 = 42. As noted in the previous report, we started again to get Santiago passes, which restores some of the flexibility in telemetry scheduling. SXT OBSERVING SEQUENCE TABLES ============================================================== JST Day UT Date & Time Pass Table ID -------------------------------------------------------------- Monday PM 19-FEB-01 11:43 3 010219 P3 ARS1 STD Tuesday PM 20-FEB-01 06:42 1 010220 P1 ARS0 QS Tuesday PM 20-FEB-01 11:46 4 010220 P4 ARS0 QS-DIF Wednesday PM 21-FEB-01 06:44 1 010221 P1 ARS1 DARKCAL Wednesday PM 21-FEB-01 11:49 4 010221 P4 ARS1 STD Thursday PM 22-FEB-01 08:28 2 010222 P2 ARS1 STD Friday PM 23-FEB-01 08:31 2 010223 P2 ARS1 STD Saturday PM 24-FEB-01 05:11 1 010224 P1 ARS0 STD Monday PM 26-FEB-01 10:22 4 010226 P4 ARS1 STD Tuesday PM 27-FEB-01 03:39 1 010227 P1 ARS2 DARK137 Tuesday PM 27-FEB-01 08:43 4 010227 P4 ARS2 DIF+137 Wednesday PM 28-FEB-01 05:22 2 010228 P2 ARS2 JOP137 Thursday PM 1-MAR-01 05:25 2 010301 P2 ARS2 JOP137 Friday PM 2-MAR-01 07:10 4 010302 P4 ARS2 VLA Saturday PM 3-MAR-01 03:49 2 010303 P2 ARS1 STD Monday PM 5-MAR-01 05:36 4 010305 P4 ARS2 VLA Tuesday AM 6-MAR-01 00:34 1 010306 P1 ARS0 DARK137 Tuesday PM 6-MAR-01 07:21 5 010306 P4 ARS1 DIF Wednesday PM 7-MAR-01 03:59 3 010307 P3 ARS0 JOP137 Thursday AM 7-MAR-01 22:59 1 010307 P1 ARS1 STD* Thursday AM 8-MAR-01 02:20 3 010307 P3 ARS2 VLA* Friday AM 9-MAR-01 02:23 3 010308 P3 ARS0 JOP137* Saturday AM 10-MAR-01 00:44 2 010309 P2 ARS1 STD* -------------------------------------------------------------- Data reformatting is complete through 3-Feb-2001 (week 01_05). OBSERVING SEQUENCES: In order to have a better temperature determination on SXT data, we ran a PFI sequence that included all the five analysis filters, when we observed the target region of JOP 137 (AR 9371). It was suggested by H. Hara that we should try to get EM for given temperatures rather than to adopt two-temperature models. SCIENCE NUGGETS: 23-Feb-01: "Two-stage dimming" - Based on new data, it is suggested that yet another type of X-ray dimming was found, but the relation between the first and second dimming events is not clearly understood. 2-Mar-01: "The temperature of active region loops" - An attempt to go beyond accepting the "filter-ratio temperature" for active-region corona. It is important to see the effect of ~1.5 MK plasma in SXT data for a better characterization of hotter plasma. 9-Mar-01: "CME and an impulsive flare" - A short-duration flare (M7) was observed on 10-Mar-2001, which was associated with a CME. A compact parasitic polarity area seems to have been responsible for the event. The full list of recent nuggets is kept on http://isass1.solar.isas.ac.jp/sxt_co/index.html and the current week's nugget also normally resides on http://isass1.solar.isas.ac.jp/sxt_co/SXTweekly.html For the complete nugget archive, see one of the following sites. http://isass1.solar.isas.ac.jp/sxt_co/index.html PERSONNEL: N. Nitta arrived on 19 February. H. Hudson returned on 3 March from Europe. G. Slater departed on 19 February. VISITOR: Steve Kahler arrived for a two-month stay. Although his main objective is to study coronal hole boundaries with SXT data, he is providing extremely useful suggestions for studies of coronal mass ejections on the basis of his vast experience in the field. TOHBANS (spacecraft operators) Tohbans for week 8 SSOC: S. Masuda, H. Takahashi KSC: Y. Hanaoka, T. Ishii SXT_CO: A. Takeda, N. Nitta SXT_SW: J. Bartus Tohbans for week 9 SSOC: M. Shimojo, T. Naito KSC: S. Akiyama, T. Ishii SXT_CO: N. Nitta SXT_SW: J. Bartus Tohbans for week 10 SSOC: M. Miyashita, H. Hara KSC: S. Akiyama SXT_CO: N. Nitta SXT_SW: J. Bartus