Calibration Data

The raw calibration data from which the CALDB files are built is accessible from the Chandra Instruments and Calibration page. It is generally not recommended that you use this data for analysis, but it may be useful to know the scientific basis of the original calibration.

The "Calibration to CALDB File" pages - listed below - can also be used to trace the CALDB data from its source. Due to the size of the tables, there is a separate page for each instrument:

Analysis Notes

Matching CIAO and CALDB Versions

CALDB 4.10.4 should not be used unless you are running CIAO 4.12 or later versions!

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

News

Previous Items

22 Mar 2023 [New]

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

CfP Cycle 25 Release Cycle 25 PIMMS Effective areas information, ACIS and GRATING sample (G)RMFs and (G)ARFs for proposal planning by non-CIAO users.

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.