ACIS Instrument Support - Monthly Progress Report for September 2007

1.  ACIS Characterization

1.1 Characterize and model radiation damage in ACIS CCDs

  ...  Continued work on a paper presenting the results of the 
radiation damage/reverse annealing tests done at GSFC in 2005.

  ...  Executed new SI modes which allow more grades to be 
telmetered.  These SI modes will be used to compare TE and CC 
mode grade rejection to help calibrate CC mode.  Four ObsIDs 
(58231, 58208, 58205, 58191) in September.

  ...  Submitted abstract on temperature-dependent CTI-correction
for Chandra Calibration Workshop.

1.3 Monitor scientific on-orbit performance of ACIS

  ...  Continued investigation of bias artifacts believed to be
due to long-lived cosmic ray afterglows.  Submitted abstract
on bias artifacts and "superbiases" for Chandra Calibration Workshop.

  ...  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)

  ...  Prepared slides for October Chandra Quarterly Review. 
Rescheduled for November.


2.  Engineering

2.1 Instrument hardware engineering performance

  ...  Continue to monitor long term ACIS instrument performance.
The ACIS instrument continues to operate in nominal fashion.

  ...  The thermal tests of turning off the Detector Housing heater  
proceeded much as expected, with the final temperatures being within  
the range predicted.  Under normal operating conditions the  
performance of the instrument remains unchanged.

2.2 Flight software maintenance

2.3 Instrument science performance

  ...  Participated in monthly ACIS operations meetings.  Reviewed
proposed tests of the ACIS detector housing heater and disucssed
test results.

  ...  Reviewed documents and CAPs related to a set of tests which 
would turn off the ACIS detector housing heater.  

  ...  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).

  ...  Answered user questions about stability of ACIS gain on
short timescales.

  ...  Assisted user in accessing calibration source data from the
Chandra archive.

3.2 Provide data analysis support

  ...  Participated in CXC Cal/Ops modeling discussion group.

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


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:

Mentor to high school students participating in the Chandra 
Astrophysics Institute (C. Grant)

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