ACIS Instrument Support - Monthly Progress Report for January 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.  Reviewed trends in engineering data for the past 60 days; no unexpected trends were seen.

  ...  The EEPROM checksum was verified in the JAN1121A 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.  The trigger level may need to be lower in the next year.

  ...  Continued work on developing and testing a QEMU ACIS processor emulator. 
On-going QEMU ACIS emulator development, involving:
 -- Continued programmer manual reference process (man pages)
 -- Continued bug fixes (debugging issues with BEP A/B switching)
 
  ...  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 performaning a science run, and estimated minimum integration times.

2.3 Instrument science performance

  ...  Following a data breach on the acis web server, moved all services to acisweb.mit.edu, a dedicated virtual machine that is better protected against attack.  No Chandra data was compromised. On-line access to ACIS hardware documentation was disabled at the same time.  Working to restore all ACIS functions ASAP.

  ...  Participated in monthly ACIS operations meetings.  Discussed migration of acis to acisweb.mit.edu, and thermal issues associated with upcoming low perigee in 2023.

  ...  Participated in ACIS operations review of ACIS radiation environment and operational response to elevated radiation.

  ...  Participated in SOT radiation working group telecon.

  ...  Continued daily quick-look processing of ACIS telemetry and maintained Web interface to ACIS real-time data.  Final testing of pipeline on 64-bit Linux.  Pipeline was running in parallel on old and new hardware for comparison, now switched entirely to new system.

  ...  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 status of time dependence gain calibration and whether additional warmer data can be included without skewing results.

  ...  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.  Remotely checked on status and restarted display server.  

4.2 Generation of commands for ACIS observations

  ...  Reviewed configuration of all currently scheduled observations and checked for missing SI modes.

  ...  Worked with USINT on general philosophy of adding optional chips, cost/benefit of larger FOV versus potentially higher focal plane temperature and reduced performance.

  ...  Worked with USINT on complicated configuration for a pulsar with a thermal remnant background, answering questions about spatial distribution of contaminant and spectral resolution performance.

  ...  Worked with USINT setting up configuration for DDT observation (approved but then pulled due to source brightness)

  ...  Diagnosed issue with chip drop count and SI mode disagreement in OCAT.  Due to ACIS ops error which was quickly fixed.

  ...  Reviewed FEB0121A command load, FEB0121 final OR list, FEB0821 preliminary schedule, and FEB1521 LTS OR list.

  ...  Dropped chips from 6 ObsIDs.

  ...  Checking on automated processes associated with SACGS.