SSOC TOHBAN REPORT FOR WEEK 20 (16 May - 23 May 1994) K. MARUBASHI and K. HORI 1. SOLAR ACTIVITY The solaar activity was generally low throughout the week. The GOES background had been decreasing below B level toward the weekend. The GOES_SUMMARY plot says the biggest flare of the week (as of the end of 21-May) was the B9.4 flare at AR 7726 (peak 00:04:00 17-May). 2. STANDARD OPERATIONS 2.1 OG Write Date(UT) Pass Purpose ------- ---- ------- May 17 9400517-0619 Change BCS sequence in KSC LOS and DSN LOS 2.2 SXT Table Uploads Date(UT) Pass ID -------- ---- -- May 16 940516-0825 940516 P2 FIX CE TST May 17 940517-0722 940517 P2 ARS1 STD+LONG May 18 940518-0930 940518 P4 ARS1 DKCAL May 19 940519-0620 940519 P2 FIX CE OBS-1 May 20 940520-0721 940520 P2 FIX CE OBS-2 May 21 940521-0618 940521 P2 ARS1 STD+LONG 2.2 STT Timer Set Executed on 17 May, Pass 2. Next STT Timer should be set by 24 May. 2.3 QUIET RATE MEDIUM in SAA. QUIET RATE MEDIUM/HIGH cmmands were manually inserted to OP according to the rule (see 2.3 of SSOC Tohban Report for Week 17). However, we had to relax this rule sometimes for SXT terminator image observation. Also, we inserted unnecessary MED/HI commands sometimes. 2.4 Weekend Operation We took the Method 2 "Write two OPs for Saturday" (p. 37 of Yohkoh Tohban Duties Manual, English), because 128 commands could not cover all passes from Friday pass 1 to Saturday pass 5. 3. SPECIAL OPERATIONS 3.1 SXT Chromospheric Ejection Campaign The observation started on 19, May and interrupted on 21, May, Saturday. The SXT table originally planned to upload on Saturaday pass 2 was replaced with a standard ARS1 table for the weekend.. 3.2 BCS Recovery: on pass 2 16-May, Monday. 3.3 BCS Calibrations BCS STIM Cal on pass 2, 18-May (Wed) by ROGs 63H and 64H BCS Source Cal at 11:28 18-May by inserting OGs in OP 4.1 A 4. ERRORS AND PROBLEMS 4.4 SXT errors An SXT BIT MAP error was found on pass 1 20-May (PASS 940520-0617) and recovered on the same pass by Yobi-C command. 5. DSN Communications 5.1 Arrival Dates of Schedules Final for Week21 (Thur), Preliminary for Week 22 (Fri), but Strawman ffor Week 23 (Saturday, 1 day behind the schedule) 5.2 Data Lost DOY/BOT DSS REASON -------- --- ------------------------------------- 135/0710 16 T3C1 failed to lock (5.3 min loss) 129/2308 66 Bad Analog Tapes (5.3 min loss) (incorrect block size, unrecoverable) 131/011119-011623: 96.82% of the blocks were recovered by P/B from analog tape (many gaps included). 5.3 DSN Pass Schedule They canceled 7 contacts on the preliminary schedule for week 22. The cancel of 4 requested contacts on 4-Jun (Sat) might be the most serious problem. We canceled 5 unnecessary DSN contacts. 6. YOHKOH/ASCA Pass Conflicts There is no YOHKOH/ASCA pass conflict in the next week (w21). Actually, we selected earlier 5 passes out of 6 (negotiated at KSC). We did not consult the program prepared by Hara-san, which is mentioned in SSOC Tohban Report for Week 19. We hope that the agreement be written out again clearly, and added to the Toban Mannual or sticked on the whiteboad. 7. HIKITSUGI 7.1 Tohbans for W21 (May 23 - May 30): SSOC: Sakao, X., Xxxxxx, X. KSC: Fukushima, H., Shimojo, X. 7.2 STT Timer should be set on May 24. 7.3 Manual insertion of QT RATE MEDIUM/HIGH should be continued. 7.4 You should check the DSN contact schedule as soon as practical, especially for week end schedule. 7.5 You have to consult with Nagase san(schedule manager of ASCA team) when you decide the next week schedule. He is at room 1611, ext.2811. 7.6 Remember to delete and condense old files on the Mainframe once each week. END OF REPORT