To:sot_shift from: Dan Schwartz date: 02 Nov 99 , 11:00am EDT Subject: SOT shift report, Shift L102 -------- See http://asc.harvard.edu/acis/SOT_reports/sot-shift.html, or /proj/ascwww/AXAF/extra/science/htdocs/acis/SOT_reports/Nov_02_1999_L102.txt. Shift L102. Start at 306:12:00 GMT = 07:00am 02 Nov EDT End 12:00 noon 02 Nov SOT Lead DAS Spac/Aspect FOT/Sci liason HRC ACIS (Times will be given in GMT on day 306. In general times are rough, not precise.) PLAN Continue running under P24c. Expect to be observing Hydra A, OBSID 576, and then RX J0911.4+0551, OBSID 419. Both are imaging on ACIS-S EVENTS Status at LOS, 306:04:54, was as follows: PCAD MODE = NPNT CONTROL LAW FLAG = NPNT Stars: = 5 FIDS = 3 RA = 70.367 deg DEC = -2.887 deg ROLL = 61.561 deg Format = 2 OBSID = 763 SIM FA = -467 SIM TSC = 75623 (ACIS-S) HETG = OUT (81.0 deg) LETG = OUT (81.0 deg) HRC-S HV is ON EPHIN: A-Leak = 0.1880 mu-a B-Leak = 0.0280 mu-a 14:00 AOS Status at 306:14:42:34, was as follows: PCAD MODE = NPNT CONTROL LAW FLAG = NPNT Stars: = 5 FIDS = 3 RA = 139.537 deg DEC = -12.121 deg ROLL = 77.766 deg Format = 2 OBSID = 576 SIM FA = -467 SIM TSC = 75623 (ACIS-S) HETG = OUT (81.0 deg) LETG = OUT (81.0 deg) HRC-S HV is ON EPHIN: A-Leak = 0.1760 mu-a B-Leak = 0.0280 mu-a 15:00 LOS Next Comm expected 22:00 to 22:45 GMT (= 5:00pm to 5:45pm EST) NOTES/ISSUES/PROBLEMS MIT EGSE showed FEP3 alarms -- Jim Francis investigated and showed it was just due to squirt dropouts. From the 9am status meeting: New GRETA PCs being set up in OCC. One is available to be installed in Porter. Patch to use the side B grating potentiometer readout is prepared and ground tested. Plan to install on spacecraft and test in tomorrow morning pass. Interested parties to be notified by Bruce Twambly. Dan Shropshire has a CAP to upload an update to the on-board ephemeris. The latter has gotten completely out of date. Has no effect, except for the effect of the wrong stellar aberation correction on the bias update. This might possibly effect the one-shot attitude updates. Both Dan and myself were surprised that the aberation correction was turned ON, we had previously discussed with TRW/west PCAD and thought the concensus was to leave it off, and also not to make the aberation correction to the X-ray data. (As long as stars and X-rays are treated the same we are okay.) The "enhanced dither" patch, to keep dither operating at all times, including slews, has been regression tested on at the West coast Software Maintenance Facility (SMF)and is ready to be sent here. We need to plan time for testing here next week, using ASVT. Then we need about an 8 hour contact for the actual loading and testing on the spacecraft. MPS and the science teams need to appreciate the implementation: in normal planning we cannot specify separately the dither which is applied in a pointing and in the slew leading to that pointing. We still have the same controls over dither parameters, including zero amplitude. One primary implication is HRC HV remains ramped up as long as dither is enabled. Load P25 to be reworked to include a followup observation of the TOO SN1999em. CXC data system ops has processed part of the observation of the NGC1637 TOO, and verifies that proper data was acquired. From IAU Circular 7296 I get the position of the SN 1999em to be RA = 70.3627, and dec = -2.8626. These are the coordinates requested in the OR (P24_TOOB.or). I note we pointed about 1.5 arcmin away at RA = 70.3672 deg, DEC = -2.8870 deg. THIS IS due to the correction for boresight, it is the star tracker which is the quoted pointing direction, and the HRMA axis which is correctly pointed to the desired target! ------------------------------------------------------- Dan Schwartz, MS #3 das@head-cfa.harvard.edu phone: (617)495-7232 FAX: (617)495-7356 cell phone: (617)512-5627 pager: 800-759-8352 PIN 1636502 or e-mail 1636502@skytel.com -------------------------------------------------------