ACIS Instrument Support - Monthly Progress Report for December 2010

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, spectral 
line centroid and width, and focal plane temperature.  Updated 
monitoring web pages.  (http://space.mit.edu/~cgrant/monitor.html)

  ...  Examining further how shorter exposure times (< 5 ksec) yield
biased CTI measurements.  Added new exposure time filters to other 
monitored quantities that demonstrated biases or significant 
increased scatter.

  ...  Made improvements to the line fitting algorithm used in 
trailing charge and quantum efficiency monitoring.  The results are
more robust to data with poor S/N.

  ...  Created web page for examining bias data before and after recent
Crab observations.  No changes have been seen.

  ...  Continued work on a paper combining CTI and background monitoring
results from ACIS and Suzaku.  Assembled a list of key reference papers.


2.  Engineering

2.1 Instrument hardware engineering performance

  ...  Continue to monitor long term ACIS instrument performance. 
All ACIS engineering parameters continue to operate within predicted
limits.

2.3 Instrument science performance

  ...  Continued investigation into whether ACIS can act as it's own
radiation monitor, prompted by action from the thermal working group
which is concerned about the continued degradation of EPHIN.  ACIS
software patch is being tested on the ACIS Engineering Unit.

  ...  Participated in monthly ACIS operations meeting.  Discussed
modeling of ACIS temperatures and using ACIS as a radiation monitor.

  ...  Participated in radiation working group telecon.

  ...  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 modeling discussion group. Discussed 
testing of temperature-dependent CTI correction software in CIAO and 
CC-mode calibration.

  ...  Participated in planning telecon for upcoming meeting of
IACHEC (International Consortium for High Energy Calibration).

  ...  Validated CTI numbers used on the CXC webpages and the Chandra POG.

  ...  Commented on the new ACIS calibration information web page (not
yet public).  Suggested additional references and topics.

  ...  Reviewed testing page for acis_process_events with the new
temperature-dependent CTI correction.  Looks good!

  ...  Provided ACIS grade branching ratio information for future
support of sub-pixel positioning in MARX

  ...  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.


Outreach:

None