ACIS Instrument Support - Monthly Progress Report for December 2003

1. ACIS Characterization

1.1 Characterize and model radiation damage in ACIS CCDs

  ...  Continued taking a series of data in full-frame raw mode for
performance verification and monitoring.  Two ObsIDs this month
with data in the ACIS-S configuration.

 [...] Worked with PSU to update the time-dependent CTI information 
in their CTI corrector.  First release (ca. Summer 2002) modeled
CTI increase as a single linear function.  The new model includes
two linear functions and a step-function increase.  Implementation
underway.

1.2 Monitor scientific on-orbit performance of ACIS

 [...] Continued study of the step-function CTI change associated with
the Halloween CME.  Analysis is ongoing.  
(http://space.mit.edu/~cgrant/cti/change/change.html)

  ...  Continued examining a new model for the ACIS contaminant suggested
by Dan Dewey which could reconcile the discrepancy between the
absorption time dependence measured by the cal source and by LETG.

  ...  Continued monitoring of ACIS CTI.  Updated CTI monitoring web
page (http://space.mit.edu/~cgrant/cti/).

  ...  Continued monitoring of ACIS gain.  All CCDs stable with a slow 
decline in gain slope (ADU/eV) except for I2 which continues to vary.
(http://space.mit.edu/~cgrant/gain/).

1.3 Update and improve CCD simulation

  ...  Continued work on improving FI and BI CCD models and CTI simulation 
code.


2. Engineering

2.1 Instrument hardware engineering performance

  ...  Continue to monitor long term ACIS instrument performance.
No new anomalies or trends

2.2 Instrument science performance

  ...  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.

 [...] Participated in ACIS telecon on the possible ACIS bakeout.
Worked with Scot Anderson of LMA to set up the venting analysis of
ACIS and the OBA cavity.

 [...] Attended contamination peer review at GSFC in late October.


3. CXC Support

3.1 Provide user support

 [...] Reviewed the ACIS chapter of the Proposers' Observatory Guide 
for cycle 6.

  ...  Updated ACIS memo listing calibration ObsIDs and observation
characteristics (ACIS Memo #165).

3.2 Provide data analysis support

  ...  Continued knowledge transfer between instrument team and CXC
on calibrating the CTI model used in CTI correction and in response
matrix generation.

 [...] Participated in CXC Cal/Ops RMF discussion group.  Presented
updates on CTI and gain changes due to the Halloween CME.

  ...  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.


all recent memos available at http://space.mit.edu/ACIS/iacis.html