CalDB 4.11.3 Public Release Notes
Public Release Date: 21 AUG 2024
SDP Installation Date: 2024-08-21T16:03:22 (UTC)
I. INTRODUCTION
CalDB 4.11.3 is an upgrade to the Chandra CalDB, which includes the following items:
For the CIAO 4.16 / CalDB 4.11.3 release notes see How CalDB 4.11.3 Affects Your Analysis.
II. SUMMARY OF CHANGES
A. HRC-S QEU Version N0019
| Location: | $CALDB/data/chandra/hrc/qeu/ |
| Filenames: | hrcsD1999-07-22qeuN0019.fits hrcsD2000-01-01qeuN0019.fits hrcsD2001-01-01qeuN0019.fits hrcsD2002-01-01qeuN0019.fits hrcsD2003-01-01qeuN0019.fits hrcsD2004-01-01qeuN0019.fits hrcsD2005-01-01qeuN0019.fits hrcsD2006-01-01qeuN0019.fits hrcsD2007-01-01qeuN0019.fits hrcsD2008-01-01qeuN0019.fits hrcsD2009-01-01qeuN0019.fits hrcsD2009-09-15qeuN0019.fits hrcsD2010-09-14qeuN0019.fits hrcsD2012-03-29qeuN0019.fits hrcsD2012-10-05qeuN0019.fits hrcsD2013-09-21qeuN0019.fits hrcsD2015-02-17qeuN0019.fits hrcsD2016-02-22qeuN0019.fits hrcsD2016-07-29qeuN0019.fits hrcsD2017-01-25qeuN0019.fits hrcsD2017-06-06qeuN0019.fits hrcsD2017-09-27qeuN0019.fits hrcsD2018-01-20qeuN0019.fits hrcsD2018-05-27qeuN0019.fits hrcsD2018-09-27qeuN0019.fits hrcsD2019-02-25qeuN0019.fits hrcsD2019-08-23qeuN0019.fits hrcsD2020-01-18qeuN0019.fits hrcsD2020-07-23qeuN0019.fits hrcsD2021-05-14qeuN0019.fits hrcsD2021-09-03qeuN0019.fits hrcsD2022-09-09qeuN0019.fits hrcsD2023-09-08qeuN0019.fits hrcsD2024-03-04qeuN0019.fits |
A new version of the HRC-S QEU file set (N0019) has been generated for release in CalDB. This version adds a new QEU file, effective 2024-03-04T00:00:00 UTC, based on the most recent HZ 43 observation (28427, from June 2024.) This version can completely replace all previous distributed CalDB versions, which can then be removed from the CalDB distribution.
See the HRC QE / QE Uniformity why page for more information.
PIPELINES/TOOLS AFFECTED:
The SDP pipeline procedure tg_mk_responses is used to generate single-source GARFs and GRMFs for HRC-S/LETG observations, to be ingested onto the archive. This procedure uses the HRC-S QEU library as loaded from the ARDLIB.
See the CIAO scripts mktgresp, and fluximage, this latter which uses mkinstmap.
THREADS AFFECTED:
For exposure-corrected imaging analysis with HRC-S, see the thread:
For grating spectroscopy with the LETG/HRC-S, see the thread:
B. PCAD ACA-P DARK_CURR Update #7
| Location: | $CALDB/data/chandra/pcad/dark_curr/ |
| Filenames: | acapD2024-04-16darkN0002.fits acapD2024-05-15darkN0002.fits acapD2024-06-28darkN0002.fits acapD2024-07-25darkN0002.fits |
The CXC Aspect Team has generated a seventh set of ACAP DARK_CURR files, including four new files, to support ACA background calculation and subtraction in the ASPECT L1 pipeline. The DARK_CURR files draw on an ever-growing database of ACA full field dark current data products which have been accumulated since the 1999:223 OAC dark current pixel map. Each version N0002 dark current fits file in the CALDB includes a 1024x1024 image with the processed full-field dark current map of the ACA CCD in e-/sec. Each file also includes header information with the ACA CCD temperature of the calibration, the reference date of the ACA dark current product, and the scale expected to be used to scale the calibration e-/sec to the effective e-/sec at the observed temperatures during observations.
The DARK_CURR files have effective dates (Cal Validity Start Date, or CVSD*) which are spaced ~2-6 weeks apart, as with their previously released datasets. The new files are effective as of the respective dates given above. These new files extend the date coverage for archival observations through 2024-07-25T00:00:00, with the final file being the one that will be the default file in standard data processing (SDP) until the next release/extension.
PIPELINES/TOOLS AFFECTED:
PCAD L1 Pipeline tool asp_get_calib calls for the ASPECT CalDB files, including DARK_CURR.
THREADS AFFECTED:
None.
III. TECHNICAL DETAILS
A. HRC-S QEU Version N0019
The HRC-S QEU N0019 file set adds one additional QEU file, effective 2024-03-04T00:00:00 UTC, based on the most recent HZ 43 observation (28427, from June 2024.) The wavelength-independent drop in QE since the previous November 2023 observation is 2-3.5%, depending on dispersed orders. The wavelength-dependent corrections required on S1 and S3 continue to follow long-observed trends.
The data used to derive the previous two wavelength-dependent models (2022-09-09 and 2023-09-08) have considerably better statistics than was previously the case. The plots in Fig. 1 below give wevelength-dependent corrections applied to each file, with the black traces for S1, the red for S3.
