ACIS Instrument Support - Monthly Progress Report for June 2020

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).

  ...  Analyzed new raw mode frames and posted to http://space.mit.edu/home/fergason/acis/raw.html.

  ...  Finished setting up new laptop and associated equipment to replace failing laptop used to support ACIS operations and instrument monitoring.


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 JUN0820A load.   Will continue to run monthly.  MIT telemetry processing will automatically check the results and send out an alert if the checksum is unexpected.

  ...  The ACIS Engineering Unit remains powered off, which is the safest long-term unsupervised state.  This imposes a moratorium on new SI modes for observers, testing new FSW patches, and testing anomaly scenarios until campus access is restored.  Beginning internal discussions about when to start powering up and testing the EU.


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 may have flattened out and started decreasing recently, potentially indicating the end of solar minimum.

  ...  Began work on developing a QEMU ACIS processor emulator.  The emulator could replace EU testing, or be used to do preliminary flight software patch work before running on the EU.

  ...  Restarted team review of ACIS Flight Software User's Guide using the new version B released in April.

  ...  Reviewed documentation of ACIS data flow through the FEPs, the BEP, and various on-board telemetry buffers.

2.3 Instrument science performance

  ...  Participated in monthly ACIS operations meetings.  Discussed the Annual Thermal and Constraints Briefing, ACIS thermal model calibration, plans for re-opening MIT and powering on the EU, and access to the Wayside OCC.

  ...  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 calibration at warmer temperatures, using astrophysical sources for gain calibration, ECS statistics, and taking ECS data during the science portion of the orbit.

  ...  Reviewed a SAR to schedule cold ECS time during the science orbit.

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

  ...  Participated in a planning telecon for the IACHEC meeting.  Originally planned for April 2020, postponed to September 2020, and now further postponed to April 2021.


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.

  ...  Attended OCC COVID-19 training session.

4.2 Generation of commands for ACIS observations

  ...  Submitted test plan for ACIS testing of CXCDS 10.9, including SACGS, load review scripts, and the MIT processing pipeline.

  ...  On-call technical reviewer for Chandra proposal review.

  ...  Released an improved database of ACIS command load files.

  ...  Continued working on contingency plans for how to update the ACIS ruleset and ACIS tables in the event of a FEP failure.

  ...  Tested a minor change by mission planning of the OR list format.  No issues.

  ...  Answered FOT question on SI modes adjacent to rad zone crossing and whether the bias can be reused.  The answer is no, because you've powered down FEPs for thermal reasons.

  ...  Reviewed JUN1520A command load.  Reviewed JUN2920 LTS OR list, JUN2220 preliminary schedule, and JUN2220 final OR list.

  ...  Assigned 2 SI modes.

  ...  Checking on automated processes associated with SACGS.