ACIS Instrument Support - Monthly Progress Report for February 2009

1.  ACIS Characterization

1.1 Characterize and model radiation damage in ACIS CCDs

  ...  Continued work on irradiation/annealing tests done at GSFC
in 2005.  Retrieving additional raw data from tape and dealing with
tape drive issues.  


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)

  ...  Presented ACIS instrument status at ACIS team meeting in 
State College, PA.

  ...  Resumed collecting occasional raw data frames.  Raw frames can
be helpful with diagnosing future problems and better understanding
cosmic ray artifacts.  Examined new raw frames and posted movies to
the web.  (http://space.mit.edu/~fergason/acis/raw.html)

  ...  One observation of ACIS calibration source in CC mode to further
test the new flight software patch.

  ...  Participated in discussion of ACIS contamination calibration
including possible systematics in the ECS measurements and results
from calorimeter measurements of a sibling radioactive source.  Continued
investigating presence of fluorine on ACIS calibration sources with
manufacturer.

  ...  Reanalyzed ECS CTI measurements with reduced statistics to 
get a better sense for our sensitivity to CTI change in the future.

2.  Engineering

2.1 Instrument hardware engineering performance

  ...  Continue to monitor long term ACIS instrument performance. 
ACIS engineering continues to report nominal operations.

2.2 Flight software maintenance

  ...  Investigated FEP reset anomaly during a CC mode graded
observation (ObsID 10275).  Discussed reverting to previous
flight software version, but decided to stay with current version.

2.3 Instrument science performance

  ...  Continued close monitoring of ACIS focal plane temperatures.

  ...  Participated in monthly ACIS operations meetings.  Discussed
EPHIN performance in failure mode A, the changing Chandra orbit and
ECS observation strategy.

  ...  Participated in radiation working group telecon discussing
the radiation environment during perigee as the Chandra orbit changes.

  ...  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).

  ...  In response to a user complaint, examined two observations of
a galaxy cluster.  No problems were found and suspect user is unfamiliar
with the appearance of low counting statistics data.

3.2 Provide data analysis support

  ...  Participated in CXC Cal/Ops modeling discussion group.  Discussed
updates to contamination calibration and ECS observation strategy.

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

  ...  Participated in discussion of possible new IACHEC working group
on CCD specific issues.

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 preparing a regional science fair 
entry on galaxy clusters - continuation of a Chandra Astrophysics 
Institute project. (C. Grant)

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