ACIS Instrument Support - Monthly Progress Report for October 2024


1.  ACIS Characterization

1.3 Monitor scientific on-orbit performance of ACIS

  ...  The ACIS TXing radiation monitor triggerred a shutdown of science observing three times in October.  October 9 and 27 were related to solar storms.  Oct 21 was a false trigger during an observation of the Crab pulsar.  All shutdowns were nominal.  Reviewed CAPs for long ECS runs during the downtime.

  ...  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).

  ...  Submitted a SAR (special activity request) for new raw mode runs.  Completed during November.

2.  Engineering

2.1 Instrument hardware engineering performance

  ...  Continue to monitor long term ACIS instrument performance.  Engineering trending over the past 60 days is nominal.

  ...  The EEPROM checksum was verified in the OCT0724A loads. Will continue to run monthly.  MIT telemetry processing will automatically check the results and send out an alert if the checksum is unexpected.

  ...  Continued weekly physical audit of the ACIS Engineering Unit lab.  Weekly audits were nominal. 

2.2 Flight software maintenance

  ...  ACIS flight software patch H-J-K uploaded on September 19, 2023.  First new patch set since August 2022.

  ...  The TXing trigger during the Crab observation was due to a previously unknown bug in the exposure time calculation in a very small subset of observations.  An update to the FSW to correct this bug is under development.  Future observations of the Crab will use a different SI mode.

  ...  We continue to monitor threshold crossing rates which dropped further necessitating a new set of TXing parameters, which were uploaded on Oct 20, 2024.  The previous set dated from May 2024. Reviewed the associated CLD file.

2.3 Instrument science performance

  ...  Participated in monthly ACIS operations meetings. TXing rate updates, DS10.13 testing, cycle 26 SI mode assignment, and the unexpected TXing trigger during observation of the Crab, plus the usual updates.

  ...  Updated alerts produced by SAO pmon to remove direct use of email-to-SMS text, which has now been superceded by OpsGenie.

  ...  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 web page (http://acisweb.mit.edu/asc/evt-page.html), which provides the same information but is more automated.

3.2 Provide data analysis support

  ...  Discussed with SDS updates of CIAO pages on ACIS focal plane temperature variation.

  ...  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.  Restarted both EGSE machines routinely.

4.2 Generation of commands for ACIS observations

   ...  Assigned SI modes for most of cycle 26 (662 ObsIDs).  Started work with USINT to verify or update parameters for the remaining problematic configurations.

  ...  Built, tested, and installed a new SI mode for the Crab pulsar reobservation scheduled in December.  This mode removes the outlying FI CCD, which caused the false TXing trigger, and also changes the window block parameters by request from DS to bypass a bug in their pipeline.

  ...  Finished testing of ACIS command generation and downlink monitoring tools with CXC DS10.13. Submitted ACIS test report.

  ...  Participated in discussion with Mission Planning Constraints WG on skipping preliminary schedule reviews for fast "pickup" replans.

  ...  Reviewed OCT0724, OCT2124, NOV1424, NOV0424(x2), and NOV1624 LTS OR lists; OCT0724 and NOV0424 preliminary schedules; OCT0724, OCT3024, and NOV0424 final OR lists; and OCT0724A, OCT3024A, OCT2124T, and NOV0424A weekly loads.
 
  ...  Checking on automated processes associated with SACGS.