ACIS Instrument Support - Monthly Progress Report for August 2013

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)

  ...  Continued work on a paper combining CTI, FWHM and background monitoring results from ACIS and Suzaku.  Final continuity edits on paper continuing.

  ...  Reviewed slides of Steve O'Dell's SPIE presentation on contamination modeling.  Could be relevant to questions about the detector housing heater.

  ...  Ran two more ECS measurements at warmer focal plane temperatures (-115C and -110C).  Analyzed data and presented improved results to ACIS team.  Plan to continue occasional warm observations.


2.  Engineering

2.1 Instrument hardware engineering performance

  ...  Continue to monitor long term ACIS instrument performance.  All systems continue to perform nominally with no unusual trends.

2.2 Flight software maintenance

  ...  Engineering Unit currently running on a reasonably modern Solaris workstation.  Sucessfully completed testing of a Linux interface to the EU.  Making plans for purchase of identical backup EU Linux machines.
 
  ...  Engineering Change Order 36-1047 reviewed and accepted by ACIS team.  This is an update to the standard flight software patch buscrash2 which corrects a bug in the original version and effectively eliminates trickle-bias anomalies.

2.3 Instrument science performance

  ... Participated in monthly ACIS operations meetings.  Discussed updates to the buscrash2 and txings patches, new warm CTI measurements, linux migration, and Steve O'Dell's SPIE presentation on contamination modeling.

  ...  Re-examining the TXINGs triggering algorithm.  Finished memo on the two possible "improvements" to the currently used TXING - one which should increase sensitivity in a few cases and one which looks at high but decreasing rates.  Memo presented and discussed at ACIS monthly operations meeting.  Not obvious that the changes are worth pursuing and they could potential result in longer radiation shutdowns.  No plans to implement in the near future.

  ...  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 question on a purported anomaly in pipeline processed data.  What user thought were anomalies were normal S4 streaking behaviors.  What the pipeline thought was anomalies were well-understood bias features from cosmic-rays that were corrected during processing.  User should have read the V&V report which correctly described the problem and its mitigation.
 
3.2 Provide data analysis support

  ...  Participated in CXC Cal/Ops ACIS response discussion group.  Discussed CC mode calibration and the calibration plan for next year.

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

  ...  Answered question from the CXC pipeline on data taken during a recent trickle-bias anomaly.


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.  Plan for broken EGSE backup machine is to do nothing for now, but proceed with upgrades to Linux.

  ...  Migration of MIT realtime telemetry software to Linux continues.  Planning purchase of primary and backup Linux machines to replace EGSE hardware at the OCC.