ACIS Instrument Support - Monthly Progress Report for March 2015

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).

  ...  Collected materials and prepared slides for the upcoming Chandra Quarterly in April.


2.  Engineering

2.1 Instrument hardware engineering performance

  ...  Continue to monitor long term ACIS instrument performance.  Engineering housekeeping remains nominal.

  ...  On the ground, lost the A side DEA power supply in the Engineering Unit PSMC.  Proceeding to diagnose and reconfigure the EU power.  This has not affected use of the EU to do required flight configuration testing.

2.2 Flight software maintenance

  ...  Flight software patch F-G-H (improved buscrash2) uploaded in June 2014 and has continued to run with no issues.

  ...  Reviewed commands for ready-to-run ECS measurements when thermal conditions require fewer than six CCDs. 

  ...  Considering improvements to txings, or to ACIS radiation monitoring more generally, in response to potential loss of ACE real-time data.

  ...  Many discussions of ObsID 16701, an ACIS/gratings observation of GRS1915, a bright X-ray binary.  The txings count rate was high and cycling up and down.  There was some worry it could trigger a radiation shutdown, but the TXINGs patch worked as designed and did not trigger.

2.3 Instrument science performance

  ...  Participated in monthly ACIS operations meeting.  Discussed status of the ACIS Engineering Unit, progress in DEA/FEP diagnostic procedures and flight EEPROM testing, possible improvements to ACIS radiation monitoring in the event of loss of real-time ACE data, and new CTI SI modes.

  ...  Participated in radiation working group telecons.  Provided expertise on ACIS radiation detection by txings.  Discussed plans for radiation monitoring if ACE real-time data is lost. 

  ...  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 planning telecon for next IACHEC meeting (April in Beijing).  Discussed meeting logistics and working group progress.  Organizing CCD working group session.

  ...  Co-authoring and reviewing paper for the Journal of Astronomical Telescopes, Instruments, and Systems on "A synoptic view of X-ray in-flight calibration plans" a product of the IACHEC Heritage Working Group.

  ...  Answered CXC SDS question about the rate of horizontal streaking on S4 and its positive correlation to the particle background.

  ...  Discussion with CXC SDS about the size of ACIS framestore shadows.

  ...  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.