ACIS Instrument Support - Monthly Progress Report for October 2019

1.  ACIS Characterization

1.1 Characterize and model radiation damage in ACIS CCDs.

  ...  Worked on new CTI correction coefficients for FI temperature dependent CTI correction.  Discussed release schedule with SDS and CALDB manager.

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).

  ...  Began preparing materials for November Chandra Quarterly review.


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.

  ...  During ObsID 47788 on Oct 23, ACIS experienced a FEP Anomalous Reset in which all B-side FEPs were halted during bias processing.  The A-side FEPs behaved nominally.  As in previous occurrences the standard power commanding for the next run cleared the anomaly.  This was an ECS observation, so there was no science data loss.  MIT contributed with analysis of software housekeeping, command echos, and event and bias packets.

  ...  The EEPROM checksum was verified in the OCT0719A load.   Will continue to run monthly.  MIT telemetry processing will automatically check the results and send out an alert if the checksum is unexpected.

  ...  Participated in team review of quick-response anomaly web page for the DPA-B anomalous shutdown.

  ...  Followup discussion between ACIS ops and MIT ACIS regarding questions from team review of ACIS Flight Software User's Guide.  Produced more detailed document on instrument behavior when switching between BEPs.

2.2 Flight software maintenance

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

  ...  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.

  ...  Continuing forward with ACIS patch level G-H-I.  This patch makes two changes to the current F-G-H patches -- updates buscrash2 patch to force end of science run following SCS107, and adds a new deahktrip patch to respond to "red alert" DPA component temperatures.  Collecting comments on the SOT and FOT SOPs from the ACIS team.

2.3 Instrument science performance

  ...  Participated in monthly ACIS operations meeting.  Discussed the FEP reset anomaly of Oct 23, ACIS flight software patch status, and questions from the team FSW User's Guide review.

  ...  Continued daily quick-look processing of ACIS telemetry and maintained Web interface to ACIS real-time data.  Updated ACIS quick-look processing guide.

  ...  Continued to publish the "annotated DOT" timeline reports.


3.  CXC Support

3.1 Provide user support

  ...  Supported discussion of updates for the cycle 22 POG, and review of a final draft.

  ...  Answered user question about ACIS-S aimpoints, offsets, and the central gain droop.

  ...  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 the gain droop correction and testing of the next contamination CALDB update.

  ...  Answered calibration scientist's question about how ACIS event PHA values are adjusted by acis_process_events.

  ...  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.  Performed monthly check of all ACIS hardware and software at the OCC.

4.2 Generation of commands for ACIS observations

  ...  Reviewed joint XMM/Chandra observations for potential health and safety issues.

  ...  Continued to assign SI modes for remaining observations in cycle 21.  Notified USINT contacts of issues and recommended changes to configurations.  Checking for existance of chip drop contingency modes.

  ...  Reviewed OCT0719A command load.  Reviewed OCT1419 (x2), OCT2119 LTS OR lists, OCT0719 and OCT1419 preliminary schedules, and OCT0719 and OCT1419 final OR lists..

  ...  Assigned 8 SI modes.  Dropped chips from 1 ObsIDs

  ...  Checking on automated processes associated with SACGS.