SPWG MEETING MINUTES, September 19 1997

Chair: Piet Martens (ESA/SOC) Notes: Laura Allen (NASA/SOC) Attendees: Andrzej Fludra (CDS), Simon Plunkett (LASCO/EIT), Giulio del Zanna (CDS), Joe Gurman (EIT), Nat Gopalswamy (EIT), Jeff Newmark (EIT), Julia Saba (MDI), Rock Bush (MDI), Vic Gaizauskas (HIA), Karin Muglach (ESTEC), Vicente Domingo (Project Scientist/ESA) Not represented: UVCS, SUMER

1. Review of action items

- None from previous meetings - SOCs will notify campaign leaders potentially requiring MDI Hi-rate, as early as possible of need for DSN requests at least a month in advance.

2. Boundary conditions for the coming month

- October 1, SVM Reserved for Memory Dumps and TR Maintenance - 6 hours - MDI Continuous: Oct. 7 at 19:25 UT to Oct. 11, 4:35 UT. - 10-19 October Submode 3: CDS high, SUMER low. 19-27 October Submode 2: CDS low, LASCO/EIT high, SUMER low. (Submode changes depedent upon succesful completion of submode 2 and 3 upgrades at the end of September)

3. Preview of future months

- See Monthly Calendar at http://sohowww/operations/schedule/calendar.html Discussion of MEDOC campaign. Desire to avoid duplicate effort and duplicate daily meetings. We don't want daily meetings at the EOF. However, coordination may be difficult since there are several studies: JOP066, Coronal Loops, and Diagnostics of Heating Episodes in Active Regions which involve EIT and the coordinator intends to be at the EOF (not MEDOC). Therefore, we would have to have some sort of calls going back and forth. Question arose as to why we are doing this when there are no ground-based observations involved in October. The meeting asked the Project Scientist to convey these feelings to SWT in October. Reminder of the limited DSN contact on Christmas and New Year's Days. There may only be enough time to just dump the SSR, CDS was asked if they planned to reduce operations during the Christmas holiday. They may want to consider a telemetry exchange with LASCO/EIT during the 2 weeks of SUMER off, like last year.

4. Priorities for the coming month

a) Individual instrument plans ------------------------------ CDS - Emphemeral AR studies, CH campaign for a month (4 to 5 hours of observations) proposed by Giulio del Zanna, supported by EISCAT measurements. Have not heard much from EISCAT yet, they are doing observations every day depending on the sources. Low latitude coronal hole studies with Nobeyama (24 - 2 UT) and may shift synoptic program to accomadate this. Running weekly coronal hole monitoring during the weekend which will continue regularly. During a week with CDS high telemetry will either run a wide slit movie or raster movies on the limb (the higher rate would provide more diagnostic lines). Perhaps some collaboration with MDI on the wide slit movies if chosen. The wide slit movies run at a cadence of 50 or 90 seconds depending on the number of spectral lines and have quiet sun as a target. EIT also expressed an interest in collaborating. SUMER - No SUMER representative present. UVCS - No UVCS representative present. LASCO - Have EIT and HRTS calibration rockets. Have not heard much about the JOP068 which was scheduled tentatively from 29 Sept - 1 Oct; will probably not be done. HRTS has slit 1 solar radius long (one end near the pole and one near disk center). New JOP069 has been submitted which describes this. No sure that if the EIT rocket slips a day, the HRTS will also. EIT - Submitted description for their calibration rocket: Intercalibration 13. They may offpoint the rocket and request some C2 images from LASCO, otherwise just obtain LASCO C1. SEM also involved. Simultaneous data in He 304 from SEM. SUMER will be near central meridian at the time. Support JOP012/17 at beginning of October. Also added the following, which CDS will support when they can. Other instruments can use similar programs to support the Sac Peak collaboration as well as the coronal hole campaign: - October 1 -12: EIT/Sac Peak ASP/MDI/Yohkoh. EOF: Tom Metcalf Temporal Evolution of Coronal Loops 15-23 UT. Alex Pevtsov is scheduled to observe at NSO/SP using the Advanced Stokes Polarimeter from October 1 through October 12, 1997 (15:00 to 23:00 UT each day). The goal of the project ("Separator Models of Coronal Loops" by A.A. Pevtsov and D.W. Longcope) is to study temporal evolution of non-flaring coronal loops and photospheric magnetic fields in conjunction with the separator model of the coronal loops. In brief, we will use ASP vector magnetograms (2 per hour) to compute separator field lines and study their time evolution, energy output etc. We will compare these computed separators with the coronal loops observed by Yohkoh and by EIT/SOHO. We intend to use such a comparison to test the adequacy of the separator theory. The region to be observed will be selected during the campaign, but 24 hours notice will be given. A new target may be selected each day, but the target will remain the same throughout the day for ease of coordination with EIT and SXT. The size of the EIT subfield should be sufficient to cover the selected active region over the Sac Peak observing day. Also added the following to the calendar in week 41: - EIT/LASCO C2 observations of microjets at North Pole. MDI -- Priority is 3 day continuous (Oct 7-11), high resolution magnetic study. Target will be an active region if one appears in the high resolution field-of-view. Supporting various JOPS, JOP012/17. Interested in developing active regions and getting simultaneous magnetic and doppler measurements. During extended mission, keeping long continuous (60-90 days) but have the 3 day continuous per month changed to 5 days (for TRACE support) and relax when the continous can be scheduled during the month. Will have something for the SWT next month to get support from other PIs to make the extra DSN a "SOHO request" rather than just an MDI request. The 1997 3 months continuous coverage was slightly less than 95%, mostly due to some data being lost between JPL and GSFC. b) Intercalibration activities ------------------------------ Intercalibration 001 has not been run, since at the last SPWG figured that the calibration rockets were sufficient. c) Joint observing plans ------------------------ Have not received much information concerning the: 'Beginning' of October Ephemeral Active Region Study Leader: Franz Kneer (

5. JOPs status

Nothing to report

6. New JOPs

JOP069 and Intercalibration 13; discussed above

7. AOB

SOC and MDI wanted to point out the absolute importance of DSN contact scheduling. Laura Allen mentioned that during the HRTS rocket launch, there was a station handover scheduled * at * the launch time. She talked to the DSN schedulers and the handover will now be moved to ~ 20:30 UT. However, notice is really needed a minimum of a month in advance to schedule such things. MDI also included the following notice to be added to the minutes: Notice to potential MDI collaborators ------------------------------------- We remind colleagues who desire MDI support during joint observations that we can provide only 96-minute cadence, full-disk magnetograms if we do not have high-rate telemetry. MDI high-rate telemetry requires (1) being in contact with the spacecraft and (2) no concurrent recording to or dumping of the Solid State Recoder (SSR). As competition for DSN contacts increases, it becomes even more important than in the past that SOHO requests for DSN support are made at least several weeks in advance, the earlier the better. This is especially important for contact needed outside the usual period for the long contact of the day (~1400-2400 UT), but even contact within the usual long-contact period cannot be taken for granted. Typically we get high-rate data about two hours after the start of the contact; the delay depends on the length of time since we were last in contact. On certain occasions, we can get high-rate data earlier in the contact if the SSR dump is delayed, but delaying the dump delays receipt of data that may be important for planning, and so must be agreed to in advance by all the instrument teams affected. Colleagues interested in having MDI participate in collaborative observations should send an email message to, specifying the dates and times of the joint observations and the type of MDI observations preferred. There should be sufficient information in the message about the observing program and science goals that the MDI team can determine if they can support the program given other constraints and commitments. If support is possible, the MDI team will forward the request for the necessary DSN contact time to the SOHO Science Operations Coordinators. Meeting adjourned: 11:30