ACIS Instrument Support - Monthly Progress Report for March 2004

1. ACIS Characterization

1.1 Characterize and model radiation damage in ACIS CCDs

  ...  Continued taking a series of data in full-frame raw mode for
performance verification and monitoring.  Three ObsIDs this month
with data in the ACIS-S and ACIS I configurations.

1.2 Monitor scientific on-orbit performance of ACIS

 [...] Continued study of the step-function CTI change associated with
the Halloween CME.  Analysis is ongoing.  
(http://space.mit.edu/~cgrant/cti/change/change.html)

  ...  Continued monitoring of ACIS CTI.  Updated CTI monitoring web
page (http://space.mit.edu/~cgrant/cti/).

  ...  Continued monitoring of ACIS gain.  All CCDs stable with a slow 
decline in gain slope (ADU/eV) except for I2 which continues to vary.
(http://space.mit.edu/~cgrant/gain/).

 [...] Conducted tenth CTI measurement in alternating exposure mode
with frame times of 4.0 and 3.2 seconds (ObsID 60358).  Updated web
page with new analysis. (http://space.mit.edu/~cgrant/cti/altexp.html)

 [...] Presented ACIS status for Chandra Quarterly Review at MSFC

1.3 Update and improve CCD simulation

  ...  Continued work on improving FI and BI CCD models and CTI simulation 
code.

  ...  Preliminarily verified new BI QE curves.  Release a complete
set of QE files to CXC Calibration for testing and incorporation into CALDB.


2. Engineering

2.1 Instrument hardware engineering performance

  ...  Continue to monitor long term ACIS instrument performance.
ACIS continues to perform nominally; a review of the engineering data 
for the past 60 days reveals no anomalies.

2.2 Flight software maintenance

 [...] FOT/SOT review of procedure to upload ACIS flight software patch
(Rev C of Flight Software Optional Patches).  Includes smTimedLookup
which allows the submode of TE mode to be read from dynamic tables.
The CC3x3 and Event Histogram patches are modified to be consistent.  
Also includes Compress All which allows raw mode data to be telemtered
even when compression fails.

2.3 Instrument science performance

  ...  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.

 [...] Participated in ACIS telecon on the possible ACIS bakeout.


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 RMF discussion group.  Discussions
of improvements in CTI response modeling, QE and QEU interface issues.

  ...  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.


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