ACIS Instrument Support - Monthly Progress Report for March 2017

1.  ACIS Characterization

1.3 Monitor scientific on-orbit performance of ACIS

  ...  Follwing Chandra Normal Sun Mode and Bright Star Holds on March 6, 9, and 31, verified ACIS was safe, monitored housekeeping data during recovery, and supported safe mode recovery including SI mode reassignment, chip dropping, and load review.  Ran two CAPs to collect additional 130 ksec of ECS data during the shutdown periods.

  ...  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).

  ...  Released updated and corrected template CAPs and how-to-use procedures for RTS ECS CTI measurements.  Updates motivated by recent BSH/NSM shutdowns in which yielded substantial ECS time.  Fixed erroneous CLD filenames, updated DPA current verifiers, added language about testing against thermal models, improved clarity overall.


2.  Engineering

2.1 Instrument hardware engineering performance

  ...  Continue to monitor long term ACIS instrument performance.  All engineering data remains nominal.
  
  ...  The EEPROM checksum was verified in the MAR1117A load.   Will continue to run monthly.  MIT telemetry processing will automatically check the results and send out an alert if the checksum is unexpected.

  ...  Reviewed updated SOP, "4.11_V2.1 Put ACIS into thermal standby mode."  Updated to reflect current operations.

  ...  Reviewed new pre-approved CAP, "Power up all ACIS FEPs", to run the command WSFEPALLUP in the event of a safing action at a cold ACIS attitude to prevent the FEPs from getting too cold.

2.2 Flight software maintenance

  ...  Flight software patch F-G-H (improved buscrash2) uploaded in June 2014.

  ...  Examined recent TXINGs data and determined that the current "optimal" parameters are still appropriate and new parameters do not yet need to be uploaded.  Will check again in May/June.

  ...  New web page lists all ACIS CLDs and their contents, with links to the commands themselves.  Working on verifying against FOT CLD lists.

2.3 Instrument science performance

  ...  Continuing to review new ACIS quick-look anomaly reference web pages.  Updated DEA shutdown anomaly page with more detailed response actions.  Reviewed by ACIS ops and released.

  ...  As part of the review of the DPA-B shutdown anomaly response page, investigated the response of the instrument to a shutdown and restart of DPA-B during a science run that does not use the DPA-B powered FEPs with testing on the ACIS engineering unit.  Test results documented in memo: "Effect of DPA Power-Cycling during a Science Run" ftp://acis.mit.edu/pub/acis-dpab-powerdown-v1.0.pdf

  ...  Co-author on an abstract submitted to the summer SPIE meeting, "Modeling contamination migration on the Chandra X-ray Observatory IV".

  ...  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

  ...  ACIS memo listing calibration ObsIDs and observation characteristics (ACIS Memo #165) will no longer be updated.  Functionality is replaced by new web page (http://acis.mit.edu/asc/evt-page.html), which provides the same information but is more automated.

3.2 Provide data analysis support

  ...  Participated in CXC Cal/Ops ACIS response discussion group.  Discussed contamination measurement and modeling, temperature-dependent CTI correction evolution, and planning for the Chandra participation in the IACHEC meeting.

  ...  Doubled checked the contents of TCTI files in the test CALDB.  Verified they are what was intended.

  ...  Commented on TGAIN corrections versus time, which are well correlated with the CR background rate.  Provided S3 high energy reject data as a proxy.

  ...  Participated in IACHEC meeting in California.  Organized CCD and Background Working Group session.  Also attended related Mission Synergies Workshop at Caltech.

  ...  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.  Performed monthly check of all ACIS hardware and software in the TST room at the OCC.  Received and distributed new sotmaxaf EHS password.

  ...  Continued training ACIS operations personnel on the use of the ACIS EGSE machines in the absence of an expert user.

4.2 Generation of commands for ACIS observations

  ...  Continued review and updating of SACGS documentation (SACGS = SOT ACIS Command Generation System).  Updated OR list review documentation to add warnings for solar system objects or other non-standard pointing.

  ...  Continuing familiarization with SACGS operation and under-the-hood functioning.

  ...  Fixed usage message for "scandrophist" tool, used to confirm whether interrupted command loads include observations with dropped chips.

  ...  Built, tested, and released new Next-in-Line event histogram SI modes that use 4-chips instead of 5, to be used when thermal conditions require.

  ...  Reviewed MAR2717A and MAR2717B command loads.  Reviewed APR0317 preliminary schedule, final OR lists.  Reviewed APR1017 Long Term Schedule OR list.

  ...  Dropped chips from seven obsids.  Assigned three SI modes.

  ...  Checking on automated processes associated with SACGS.