SSOC Tohban Report for Week 12 (21 MAR - 27 MAR, 1994) 28 March, 1994 (Mon) A. Sterling and T. Fujiwara (SSOC) R. Kano and J. Sato (KSC) 1. Solar Activity There was only one event of C or greater size through 25-March. It was C3.6 and occurred near 22:00 on 24-March. 2. Standard Operations 2.1 SXT table uploads Date(UT) Pass ID Mar.21 940321-0928 940321 P2 ARS1 STD+LONG Mar.23 940323-1033 940323 P4 ARS1 DKCAL Mar.24 940324-0827 940324 P2 ARS2 LARGE LOOPS 940324-1033 940324 P4 ARS1 STD+LONG 2.2 STT timer set Done on Mar.22 in pass 940322-0929. Next setting due Tuesday Mar.29. 3. Special Operations 3.1 HXT Activities HXT Gain: 940325-0824 HXT Cal: 940325-0927 HXT Cal: 940325-1031 3.2 Quiet Med Mode during SAA We continued to insert QUIET RATE MED seven minutes after HV reduction on, and QUIET RATE HI seven minutes before HV reduction off, to ensure maximum data collection. If this is to be standard procedure, we may consider having Jim Lemen san add the commands to op_first_guess. Adjustable parameters Jim may consider inputing are: (a) Minimum amount of observing time to be gained that would make input of these commands worthwhile. So, e.g., if the SAA is only 15 minutes long, then inputing the QUIET RATE MED/HIGH commands probably would not be worth it, since it would only gain about one minute of observing time. Should the cut-off be one minute, three minutes, or what? The amount of "Yohkoh night" during each SAA passage will have to be factored in somehow too. (b) The number of available SAAs that the tohban wants to include the mode switch in should be another parameter. This is because sometimes adding all possible mode changes will make the OP too long. op_first_guess should tell the tohban the total number of SAAs that satisfy acceptable conditions, i.e., the condition set by (a) above, and the requirement that you have QT RATE HI mode when entering the SAA. As an example implementing (b), say that there is room for two sets of SAA mode changes in an OP, out of five SAAs that satisfy the conditions for input. Then if the tohban wants to include the mode commands in two SAAs, op_first_guess should default to adding the mode changes to the SAAs that would give the most additional data. In other words, it adds them to the two SAAs with the longest amount of daylight out of the five possible SAA choices. 4. Errors and problems 4.1 Instrument Errors No BCS SEUs or SXT errors during the week. 4.2 Network Problems As reported in last week's SSOC tohban report, there was a long interruption of network service around 20 March. Hugh Hudson san asked Jun Matsukata san who to contact in such cases. The reply was that Matsukata san himself is the person to tell. He is responsible for networking at ISAS, and can be reached at EMAIL: jm@eng.isas.ac.jp Phone (office): X 2082 (0427-51-3911 for ISAS switchboard, of course) Phone (home): 044-522-1534 4.3 ASUKA Data Asuka data was mistakenly sent to Yohkoh from KSC for ASUKA pass number 940321-0310. 5. DSN Communications 5.1 Retransmission Request On 25 March we requested retransmission of data for DOY 81, DSS 16 from 9:24 - 9:35 UT. 5.2 Cancellations We cancelled several passes for week 13 from the final schedule. Such schedule changes raise some concerns at JPL, as evidenced by the following EMAIL sent from Wendell Keller to Jim Lemen on 24-March: ---------------- James, Since seven passes were cancelled last week by ISAS, we apparently were able to schedule more passes than were desired. I assume the passes were cancelled because ISAS did not want them. Regards, Wendell --------------- I responded on 25-March by pointing out that of the eight passes we had cancelled on 24-March, seven of them had been requested to be cancelled at the strawman level, and four of them were requested to be cancelled at the Preliminary level. In his response to me on 26-March, Wendell said that he will verify that our cancellation requests received there are implemented from now on. Wendell still, however, had questions about the number of deletions the previous week (week 11). A quick survey shows that three of the six week 11 final schedule deletion requests were requested for deletion at the week 11 Preliminary schedule level. Since other satellites may have lost the chance to use the passes that were cancelled at the last minute, this issue should be regarded as important and be solved as efficiently as possible. 6. Other Wendell Keller writes in an EMAIL to Lemen san (Mar.26) that DSN is contemplation using the facilities at Wallops Island for additional Yohkoh support. That would require that ISAS be able to use the Wallops source code (hex 60). Presumably Jim will respond to this inquiry. Minor changes have been penciled into to the tohban checksheet and new copies printed. 7. Hikitsugi 7.1 DSN Passes As indicated in 5 above, we made several cancellations from the final schedule for week 13. You may find that there are still more passes then needed. We decided at the Monday meeting (28 March) that this week's tohbans will request more cancellations for week 13 if there are passes that are not really necessary. 7.2 EMAIL Please be sure to store EMAIL to and from yohkoh@flare1 in mail/mail_94_w13. 7.3 DSN Log Remember to log and file not only FAXes, but also relevant EMAIL to and from DSN. 7.4 Tohbans for W13 SSOC: M. Shimojo and G. Slater KSC: J. Sato and T. Magara