ACIS Instrument Support - Monthly Progress Report for April 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).

  ...  Prepared slides for and presented at the Chandra Quarterly.

  ...  Replied to comments on "Fifteen years of ACIS", a proceedings paper from SPIE last summer.

2.  Engineering

2.1 Instrument hardware engineering performance

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

  ...  Investigated the anomaly in the engineering unit whereby power from the PSMC DEA Side B supply was powering the instrument DEA Side A.  Resoleved the issue by rewiring the engineering unit internal cabling to match the flight prints.

  ...  Conducted successful test on the ACIS Engineering Unit of the "switch_deaa_b" flight procedure that switches PSMC power from DEA-A to DEA-B.  Ready for final team review of procedure and creating new ACIS command packets.

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.

  ...  Considering improvements to txings, or to ACIS radiation monitoring more generally, in response to potential loss of ACE real-time data.  Re-examining ACIS threshold crossings data immediately before Chandra radiation shutdowns to find any good cases that are currently missed by the TXINGs algorithm.  Required book-keeping between radiation shutdown listings kept at MIT and CXC.

2.3 Instrument science performance

  ...  Participated in monthly ACIS operations meeting.  Discussed status of 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 Doug Swartz's new contamination modelling results.

  ... Substantial discussion of Doug Swartz's (MSFC) new contamination modelling results that were presented at IACHEC.  Provides an extrapolation to the future that is troubling.  May provide some insight into the design of and probability of success of an ACIS bakeout.  Accuracy of model extrapolation is not yet clear.

  ...  Discussion of predictions for CTI & FWHM increase in the event that ACE is not available for real-time monitoring and how best to present that information to communicate the effect on Chandra science.

  ...  Participated in radiation working group telecon. Discussed rad zone timing and modeling, and 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

  ...  Attended talk on new method of creating response matrices which is being used for eROSITA and XMM EPIC-pn.  Pondering applicability for ACIS.

  ...  Participated in planning for IACHEC meeting in Beijing.  Organized 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.  Submitted second round of edits to first author.

  ...  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.