ACIS Instrument Support - Monthly Progress Report for August 2006

1.  ACIS Characterization

1.3 Monitor scientific on-orbit performance of ACIS

  ...  Continued monitoring of ACIS CTI, gain, trailing pixel 
pulseheight, detector efficiency, corner pixel distribution, and 
spectral line centroid and width. Updated monitoring web pages.  
(http://space.mit.edu/~cgrant/monitor.html)

  ...  Continued a more comprehensive study of the effect of focal
plane temperature variations on the metrics used in ACIS
monitoring.  When complete, will be used to define temperature
filter criteria more appropriate to the data.

  ...  Continued work on memo for the operations team on the 
consequences of a future, unprotected radiation belt transit by ACIS.  
Awaiting final inputs, then will circulate to wider distribution.

  ...  Presented ACIS SI team report at the Chandra Quarterly Review.

2.  Engineering

2.1 Instrument hardware engineering performance

  ...  Continue to monitor long term ACIS instrument performance.
A review of the last 60 days' worth of engineering data reveals no 
unexpected performance.  A 5 CCD observation run with only 5 DEAs and 5 
FEPs powered on showed a decrease in PSMC temperature of 5C over a 
similar 6 DEA/6 FEP case, thus validating our thermal predictions.  This 
allows the scheduling people to reduce the thermal stress on ACIS (by 
turning off unnecessary DEA and FEP channels) without additional 
attitude constraints.

2.3 Instrument science performance

  ...  Participated in "monthly" ACIS operations meeting.  Discussed
upcoming 10 video board housekeeping diagnostic run, thermal issues,
and bias anomalies.

  ...  Planned for future ACIS test which will collect housekeeping
data with all ten video boards powered on.  These data will be 
compared to that taken in 1999.

  ...  Prepared memo describing newly reported bias map anomalies
(ftp://acis.mit.edu/pub/SPR139-0.1.pdf).  Discussion at ACIS operations
meeting pointed to a possible cause outlined in a September release of
this memo.

  ...  Continued daily quick-look processing of ACIS telemetry and 
maintained Web interface to ACIS real-time data.

  ...  Continued to publish the "annotated DOT" timeline reports.


3.  CXC Support

3.1 Provide user support

  ...  Updated ACIS memo listing calibration ObsIDs and observation
characteristics (ACIS Memo #165).

3.2 Provide data analysis support

  ...  Participated in CXC Cal/Ops modelling discussion group.  
Reviewed AO-8 calibration plan, discussed new CTI-corrected response
products for S3 and S1.

  ...  Continued to maintain ACIS calibration database of ground and 
flight data products.

  ...  Answered question on grade-dependence of quantum efficiency.

  ...  Responded to query from CXC DS about data corruption in ObsID 
7006 which is due to a known ACIS anomaly (SPR138).

4.  OCC Support

4.1 Use of MIT/ACIS EGSE at OCC

  ...  Continued support and maintenance of ACIS EGSE software and 
hardware at the OCC.

  ...  Continued work on improving configuration management of the ACIS
workstations in the TST area of the Chandra OCC.  Work nearly complete.


Outreach:

None

all recent memos available at http://space.mit.edu/ACIS/iacis.html