Skip to the navigation links

Chandra Proposal Planning

The following links address known issues relating to the usage and accuracy of calibration data files included in the Chandra CalDB. These have been added on an ad-hoc basis, and are by no means exhaustive. More may be added at any time.

HRC-S QEU File Search Errors for 2014 and 1999 observations: Two errors in the CalDB index for the HRC-S time-dependent QEU files, which applies to all 2014 and 1999 HRC-S observations. A temporary workaround is prescribed.
38 ACIS archival OBS_IDs with "problem reading tgainfile" from the CalDB: A problem for certain ACIS OBS_IDs whose duration crosses an ACIS T_GAIN epoch boundary. A simple fix to the problem is prescribed.
ACIS Responses Suite version N0005: A discussion of the accuracy of the latest FI chip RMFs with mkacisrmf.
Using the HRC-I RMF: Issues regarding the use of the HRC-I RMF version N0002 in Sherpa/XSPEC.
ACIS T_GAIN FILE ERRORS: ACIS Epoch 42 (May-July 2010) T_GAIN file errors, in CalDB 4.4.1 and 4.4.2.

Analysis Notes

Matching CIAO and CALDB Versions

CALDB 4.11.5 should not be used unless you are running CIAO 4.16 or later versions!

Are your versions mismatched? Time to upgrade CIAO and CALDB!

News

21 Aug 2024 [New]

CalDB 4.11.5 has been released to the public. Included in this release are HRC-S QE version N0017, and QEU version N0020 file sets as well as two new ACA-P DARK_CURR files (periodic updates #8), which do not affect CIAO. See the CalDB 4.11.5 Release Notes for details.

21 Aug 2024

CalDB 4.11.3 has been released to the public. Included in this release is an updated HRC-S QEU time-dependent file set version 19 (34 new files), as well as four new ACA-P DARK_CURR files (periodic updates #7), which do not affect CIAO. See the CalDB 4.11.3 Release Notes for details.

06 Jun 2024

CalDB 4.11.2 has been released to the public. Included in this release is an updated HRC-I QE time-dependent file set version 15 (38 new files). See the CalDB 4.11.2 Release Notes for details.

18 Apr 2024

CalDB 4.11.1 has been released to the public. Included in this release are the new ACIS "warm-temperature" CTI corrections vN0012, and an updated HRC-S QEU N0018 file set (33 new files). Also included are set #6 of the PCAD ACA-primary DARK_CURR (dark current) image files. See the CalDB 4.11.1 Release Notes for details.

12 Dec 2023

CalDB 4.11.0 has been released to the public. Included in this release are the new ACIS "warm-temperature" CTI corrections vN0011, and an updated HRC-I QE N0014 file set (37 new files). Also included are set #5 of the PCAD ACA-primary DARK_CURR (dark current) image files and the Cycle 26 PIMMS Effective Area configuration files, neither of which affect CIAO users. See the CalDB 4.11.0 Release Notes for details.

14 Dec 2023

CfP Cycle 26 Release Cycle 26 PIMMS Effective areas information, ACIS and GRATING sample (G)RMFs and (G)ARFs for proposal planning by non-CIAO users.

14 Sep 2023

CalDB 4.10.7 has been released to the public. Included in this release are the latest HRC-S QE Uniformity data sets (version N0017) including one addtional data set effective for OBS_IDs taken after the HRC-S restart. Also included are more PCAD ACA-primary DARK_CURR (dark current) image files, which do not affect CIAO users. See the CalDB 4.10.7 Release Notes for details.

22 Mar 2023

CalDB 4.10.4 has been released to the public. Included in this release are the latest ACIS T_GAIN (time-dependent gain) updates, which will be updated annually rather than semiannually going forward. Also included with this release are PCAD ACA-primary DARK_CURR (dark current) image files, which do not affect CIAO users. See the CalDB 4.10.4 Release Notes for details.

15 Dec 2022

15 Nov 2022

CalDB 4.10.2 has been released to the public. Included in this release is the latest ACIS OBF Contamination (CONTAM) model (v N0015) upgrade, which adjusts for recent (2020-2022) increases in the contamination rate relative to the older model (v N0014). See the CalDB 4.10.2 Release Notes for details.

16 Jun 2022

CalDB 4.9.8 has been released to the public. Included in this release are PCAD ALIGN file updates (18 new files, six-month intervals, extending from 2013-2021); HRC-I/Grating angle corrections in the PIXLIB GEOM file vN0007; HRC-S QE Uniformity upgrade version N0016 with and additional new file for new observations. See the CalDB 4.9.8 Release Notes for details.

24 Mar 2022

CalDB 4.9.7 has been released to the public. Included in this release are ACIS T_GAIN upgrades for Epochs 85+86 (effective 2021-05-02, finalized) and epochs 87+88 (effecive 2021-11-01, provisional), and expanded FP_TEMP boundary conditions for certain ACIS CalDB files applicable to current and future datasets, to accommodate warmer ACIS calibration observations to be taken in the near future. See the CalDB 4.9.7 Release Notes for details.

24 Sep 2021

CalDB 4.9.6 has been released to the public. Included in this release are ACIS T_GAIN upgrades for Epochs 83+84 (effective 2020-11-01, finalized) and epochs 85+86 (effecive 2021-05-02, provisional), HRC-S T_GMAPs v4, QE v16, and QEU v15, as well as HRC-I QE v13. See the CalDB 4.9.6 Release Notes for details.

29 Apr 2021

CalDB 4.9.5 has been released to the public. Included in this release are ACIS T_GAIN upgrades for Epochs 81+82 (effective 2020-05-02, finalized) and epochs 83+84 (effecive 2020-11-01, provisional), as well as a new ACIS-S3 CTI correction file for observations taken since 2020-01-01. HRC-I/LETG +/- 1st order LSF parameter files have also been added. See the CalDB 4.9.5 Release Notes for details.

16 Dec 2020

CalDB 4.9.4 has been released to the public. Included in this release are the ACIS CONTAM N0014 upgrade, an HRC-S QEU N0014 upgrade with 29 new files for the library, and a delayed upgrade to the HRC-S PI Region background filter file N0002. See the CalDB 4.9.4 Release Notes for details.