To:sot_shift
from: Dan Schwartz
date: 21 Oct 99 , 11:00am EDT
Subject: SOT shift report, Shift L90
--------
See http://asc.harvard.edu/acis/SOT_reports/sot-shift.html, or 
/proj/ascwww/AXAF/extra/science/htdocs/acis/SOT_reports/Oct_21_1999_L90.txt.

Shift L90. 
	Start at 294:11:00  GMT
		 = 07:00am 21 Oct EDT
	End	   11:00am 21 Oct
   
SOT Lead	DAS
Spac/Aspect	
FOT/Sci liason	
HRC		
ACIS 		YMB

(Times will be given in GMT on day 294. In general
times are rough, not precise.)

PLAN
Continue running load p22e. 
In radiation belts.

EVENTS
    10:40 AOS
294:10:45 Confirm SIM in proper position, HRC-S at aim point, for
	Radiation belt passage
    12:50 LOS
Status at LOS, 294:12:49, was as follows:
       PCAD MODE              =       NPNT
       CONTROL LAW FLAG       =       NPNT
       Stars:                 =          5  
       FIDS                   =          0 
       RA                     =    130.805 deg
       DEC                    =     36.362 deg
       ROLL                   =     72.261 deg
       Format                 =          2
       OBSID                  =        532

       SIM FA                 =       -535
       SIM TSC                =     -99616 (HRC-S)
       HETG                   =        OUT
       LETG                   =        OUT
        HRC HV is OFF
        EPHIN:         A-Leak =   0.5960 mu-a
                       B-Leak =   0.1560 mu-a   

Next Comm 21:20 -- 23:00

NOTES/ISSUES/PROBLEMS

Quick Look data notes:
	Southern Deep field subsequent to intervention to 
correct the FEP bias parameters, looks fine. OBSID 1431
	Abell 2218, subsequent to intervention to remove
use of FEP 0, looks good. OBSID 1454. (The original OBSID
portion 553 using FEP 0 was also good.)
	Cyg X-3/HETG.  OBSIDs 101 and 1456 both look good. 
To my eye, the level 2 processing seems to "split" each
dispersed line down the middle. ? 
	Cyg X-1 HETG, OBSID 107, failed aspect: recognized
no stars or fid lights.
	Note that OBSID 1455 was NOT done.  This was planned
as an intervention into 107 to remove FEP 0. However, the
available parameter block was only for Faint mode, and the
observation required graded mode because the event rate
was substantially exceeding the telemetry for Faint mode.

From the 9am status meeting:
Command load p23 has problems being scheduled. Currently
not diagnosed, and we are approaching a deadline for final
review. It needs to be uploaded no later than 296:13:15--14:55
as p22e expires on 296:18:15. Tagup assessment of status 
planned for 3pm today.

Due to the very small, but measureable, 1 E-6, increase in ACIS
CTI following the last belt passage, we want to remove ACIS
from the aim point earlier during the descent into the belts,
so we will re-institute a CTI measurement prior to belt
entry starting in load P23. (Currently we did not move
SIM to HRC position until about 1/2 hour before the current
belt passage.) Note that the CTI measurements use 6 FEPs --
this may give some more diagnostic data on them.

From the 10am ACIS ops meeting:
Radiation damage has been eliminated as the source of the FEP0
problems.  Therefore the team recommends leaving the FEP power
on during the belt passages, on the rationale of not cycling
things unnecessarily.
Two experiments need to be done, via real-time CAPs, during the 
next load.  First is targeted for Tuesday morning, Oct 26, to intercept
at the start of the ACIS CTI measurement prior to belt passage.
It will telemeter all 1024 rows of 8 to 12 columns.

-------------------------------------------------------
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 
-------------------------------------------------------