ACIS Instrument Support - Monthly Progress Report for February 2021

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).

  ...  Finished porting remaining Unix-based monitoring scripts to Linux, in conjunction with the Unix->Linux switch of the ACIS quick-look processing pipeline.


2.  Engineering

2.1 Instrument hardware engineering performance

  ...  Continue to monitor long term ACIS instrument performance.  The flight system continues to report nominal engineering data.

  ...  Supported review of Chandra OBC flight software patch for ACIS thermal limit checking.  Uploaded on Februrary 12.

  ...  The EEPROM checksum was verified in the FEB0821A load.   Will continue to run monthly.  MIT telemetry processing will automatically check the results and send out an alert if the checksum is unexpected.

2.2 Flight software maintenance

  ...  ACIS flight software patch G-H-I (improved buscrash and new deahktrip) uploaded on January 24, 2020.  First new patch set since June 2014.  No issues to date.

  ...  We continue to monitor threshold crossing rates.  The current TXINGS parameters were last updated on July 28, 2016.  Threshold crossing rates have flattened out and started decreasing, indicating the end of solar minimum. We anticipate needing to lower the trigger threshold in the next year and rates continue to drop and activity increases.

  ...  Continued work on developing and testing a QEMU ACIS processor emulator. 
-- Started debug of some support tool build issues on a Linux/Mint development environment
 -- Supported ACIS EU/QEMU user documentation review
 
  ...  Continued team review of ACIS Flight Software User's Guide using the new version B released in April.  Completed sections on instrument science activities, such as estimating setup times and telemetry utilization, and started section on parameter and window blocks.

2.3 Instrument science performance

  ...  Following a data breach on the acis web server, all services were moved to acisweb.mit.edu in January.  Updated links pointing to acis.mit.edu, including installing a new version of pmon on SAO servers, and outside users that use MIT resources.  The ACIS hardware documentation tree remains off line at this time.

  ...  Participated in monthly ACIS operations meetings.  Discussed thermal issues associated with upcoming low perigee in 2023 and new limits on focal plane and cold radiator temperatures.

  ...  Participated in SOT radiation working group telecon.

  ...  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 proposed new PCA method for fitting ECS and Cas A data to calibration time dependent gain.

  ...  Updated the CTI versus temperature calibration to include a new epoch to cover 2020+.

  ...  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 Wayside OCC.  Emily was not responding to ssh and required a physical reboot (by Paul Viens who is authorized to access the control room).  Cause is unknown, could indicate a problem with the hardware, but no repeat of the problem to date. 

4.2 Generation of commands for ACIS observations

  ...  Started building custom SI modes for use for use with the ECS, allowing for more flexibility in specifying CCDs.  First mode is I0-I3.  

  ...  Worked with USINT on a complicated ACIS configuration and a TOO configuration

  ...  Checking on automated processes associated with SACGS.