ACIS Instrument Support - Monthly Progress Report for July 2015

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).

  ...  Presented poster at HEAD meeting on "The Effects of Orbital Environment on X-ray CCD Performance".  Presents what we've learned from long-term CCD performance on Chandra and Suzaku and extrapolates to future missions in LEO and L2.


2.  Engineering

2.1 Instrument hardware engineering performance

  ...  Continue to monitor long term ACIS instrument performance.  Engineering housekeeping remains nominal.

  ...  Held meeting to review ACIS operational response to PSMC power anomalies, such as the uncommanded shutdown of the DPA seen last January.  Reviewed decision trees and SOPs for a number of scenarios.  Reviews continuing.

  ...  Creating SOP to run the EEPROM checksum routine and dump the EEPROM contents.

2.2 Flight software maintenance

  ...  Flight software patch F-G-H (improved buscrash2) uploaded in June 2014 and has continued to run with no issues.

2.3 Instrument science performance

  ...  Participated in monthly ACIS operations meeting.  Discussed progress in various flight procedures, plans for turning on the DH heater long-term, plans for bakeout studies, and Chandra pointing accuracy.

  ...  FDB approved turning on the ACIS Detector Housing heater.  Wrote and submitted SAR to FOT MP to turn on detector housing heater in the command load.  Approved and will be run on August 11.

  ...  Participated in radiation working group telecon.  Discussed plans for future radiation monitoring with more limited access to ACE data.

  ...  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

  ...  Updated ACIS memo listing calibration ObsIDs and observation characteristics (ACIS Memo #165).
 
3.2 Provide data analysis support

  ...  Participated in CXC Cal/Ops ACIS response discussion group. Discussion included CC-mode QE calibration, the ACIS detector housing heater, contamination, potential future bakeout studies, and further contamination analysis.

  ...  Checked for potential radiation damage to S3 after observation of very bright source (V404 Cyg).  No evidence found of any degradation.

  ...  Discussed excess "background" seen in CC-mode ACIS+HETG observation of a bright source during a time of higher particle environment.  Believe excess events are due to a combination of cosmic ray afterglows and S4 streak events which are poorly removed when the background is high and in CC-mode.  Encouraged user to try adjusting parameters in destreak tool from the standard pipeline values.

  ...  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 OCC.  

4.2 Generation of commands for ACIS observations

  ...  Continued in training in ACIS command generation and operations procedures including load reviews, SAR/SOP creation, and TST room maintenance.  Eventually will take over some of Royce Buehler's tasks when he retires at the end of the year.