SXT Status Report October 8, 2001 - October 28, 2001 (Weeks 41-43) N. Nitta, A. Takeda, H. Hudson SOLAR ACTIVITY This three-week period started with low solar activity, but culminated in four X-class flares (two each from AR 9661 and AR 9672) during the last ten days. The first one was well observed by Yohkoh, and is the topic of the latest science nugget. The X-class flares were associated with halo CMEs, and the geomagnetic effects seemed to depend on whether the halo CME was full or partial. All the flares occurred near central meridian, and the observed modest increase in the interplanetary proton flux has to be understood taking account of possible contributions from other less intense events, especially those in the western hemisphere. OBSERVING CAMPAIGNS Yohkoh participated in three coordinated observations. One was with the Very Large Array, led by Bernhard Kliem, to observe X-ray jets (JOP 104). Second, we had better coordination with the second part of the THEMIS campaign (JOP 131/149, run by Brigitte Schmieder) to observe the onset of flares/CMEs, because more of their observing times were within the Yohkoh visible orbits. The last campaign we supported was with Sac Peak to observe transition region moss (Tom Berger). Please see our webpages for 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 There was no problem to report. Yohkoh normal pointing was adjusted on 8 and 19 October. Due to the stable pointing, we returned to the 10 minute cadence of quiet mode patrol images (from the 3 minute cadence since 11 September). TELEMETRY DOWNLINKS Week Wallops Santiago Goldstone Canberra Madrid NASA Japan 41 27 2 6 0 7 42 34 42 27 2 4 0 2 35 31 43 29 2 2 3 1 37 27 Kagoshima should average 6*5+2 = 32 and the NASA target is 7*6 = 42. SXT OBSERVING SEQUENCE TABLES ====================================================================== JST Day UT Start Time Pass Table ID Monday AM 07-OCT-01 19:59 3 011007 P3 ARS1 DFF* Monday PM 08-OCT-01 14:53 1 011008 P1 ARS0 DKJ* Tuesday AM 08-OCT-01 18:15 3 011008 P3 ARS1 STD* Tuesday PM 09-OCT-O1 14:50 1 011009 P1 ARS0 JOP* Wednesday AM 09-OCT-01 18:12 3 011009 P3 ARS1 STD* Thursday AM 10-OCT-01 18:09 3 011010 P3 ARS1 STD* Friday AM 11-OCT-01 14:43 2 011011 P2 ARS1 STD Saturday AM 12-OCT-01 14:40 2 011012 P2 ARS1 STD Monday PM 15-OCT-01 11:11 1 011015 P1 ARS2 VLA Monday PM 15-OCT-01 14:32 3 011015 P3 ARS2 VLA Tuesday AM 15-OCT-01 16:13 4 011015 P4 ARS1 DIF* Tuesday PM 16-OCT-O1 12:47 2 011016 P2 ARS1 STD Wednesday PM 17-OCT-01 11:03 1 011017 P1 ARS1 DARK Thursday AM 17-OCT-01 16:07 4 011017 P4 ARS1 STD* Friday AM 18-OCT-01 16:04 4 011018 P4 ARS1 STD* Friday PM 19-OCT-01 09:16 1 011019 P1 ARS2 JOP Friday PM 19-OCT-01 14:19 4 011019 P4 ARS1 STD Saturday PM 20-OCT-01 09:12 1 011020 P1 ARS2 JOP Saturday PM 20-OCT-01 14:16 4 011020 P4 ARS1 STD Monday PM 22-OCT-01 09:05 1 011022 P1 ARS2 JOP+TRM Monday PM 22-OCT-01 14:09 4 011022 P4 ARS1 DIFF Tuesday PM 23-OCT-O1 07:21 1 011023 P1 ARS2 JOP+TRM Tuesday PM 23-OCT-O1 12:24 4 011023 P4 ARS1 STD Wednesday PM 24-OCT-01 07:17 1 011024 P1 ARS1 DARK Wednesday PM 24-OCT-01 12:21 4 011024 P4 ARS1 STD Thursday PM 25-OCT-01 07:13 1 011025 P1 ARS2 DRK+TRM Thursday PM 25-OCT-01 12:18 4 011025 P4 ARS1 STD Friday PM 26-OCT-01 05:30 1 011026 P1 ARS2 TRM Friday PM 26-OCT-01 10:32 4 011026 P4 ARS1 STD Saturday PM 27-OCT-01 05:25 1 011027 P1 ARS2 TRM2 Saturday PM 27-OCT-01 07:09 2 011027 P2 ARS2 TRM2 Saturday PM 27-OCT-01 10:29 4 011027 P4 ARS1 STD -------------------------------------------------------------- Data reformatting is complete through September 22, week 38 of 2001. OBSERVING SEQUENCES: We reinstated the Thick Aluminum filter in the flare sequence. SCIENCE NUGGETS: October 26: "A swirling X-class flare" reports on a quick analysis of a week-old flare, making the analogy between the geometry of DNA replication and the partial eruption of a flux rope. October 19: "The relationship between hard X-ray and UV emissions in solar flares" confirms the close similarities between the two wavelength regimes, as obtained with Yohkoh and TRACE, but leaves open the question as to whether the small differences are attributable to physics or limited measurement capabilities. October 12: "Life story of a super region complex" describes the evolution of a flare-productive region over three solar rotations, giving some informative movies. 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/nuggets/ (Japan), http://solar.physics.montana.edu/nuggets/ (Montana), http://www.lmsal.com/YPOP/Nuggets/ (California) and http://ydac.mssl.ucl.ac.uk/nuggets/ (UK). SEMINARS: There was a seminar with two speakers. F. Farnik (Ondrejov/ISAS) spoke on "The Hard X-ray Spectrometer (HXRS)", and H. Hudson (SPRC/ISAS) on "The early phase of the flare of Sep. 24, 2001". Boris Somov appeared again for tea to enlighten key D-toh staffers on magnetic reconnection. PERSONNEL: H. S. Hudson and N. V. Nitta departed. Visitor F. Farnik also flew home. OTHER: We have almost completed the exodus to the annex of the ISAS main building (A-toh), thanks largely to our dedicated movers (J. Bartus and J. Khan). With a much quieter environment, we hope, our scientific productivity will significantly increase. TOHBANS (spacecraft operators) for week 41: SSOC Tohbans : T. Miyawaki, N. Shinohara KSC Tohbans : H. Adachi, K. Kobayashi, A. Ohto SXT_CO: N. Nitta SXT_SW: J. Bartus TOHBANS (spacecraft operators) for week 42 SSOC Tohbans: H. Ishizaki, H. Hara KSC Tohbans: A. Ohto, Y. Kubo SXT_CO: N. Nitta SXT_SW: J. Bartus TOHBANS (spacecraft operators) for week 43 SSOC Tohbans: H. Kozu, T. Kichiraku KSC Tohbans: Y.Kubo, I. Suzuki SXT_CO: A. Takeda SXT_SW: J. Bartus