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 4.8.5 should not be used unless you are running CIAO 4.5 or later versions.

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

News

Previous Items

07 Nov 2019 [New]

CalDB 4.8.5, an upgrade to CalDB 4.8.2 and later versions, has been released. Included is ACIS Contamination Model version N0013, with improved fitting results for ACIS modeling for observations taken since 2018. See the CalDB 4.8.5 Release Notes for details.

13 Sep 2019

CalDB 4.8.4.1, an upgrade to CalDB 4.8.2 and later versions, has been released. Included items are EMERGENCY CORRECTIONS to ACIS T_GAIN bi-epochal periods 75+76 and 77+78, which affect ACIS data sets including chips ACIS-0, 1, 2, 3, or 6 for data sets with DATE-OBS later than 2018-05-02T12:00:00. For the way to determine if your data have been affected, see the CalDB 4.8.4.1 Release Notes.

03 Sep 2019

CalDB 4.8.4, an upgrade to CalDB 4.8.2 and later versions, has been released. Included items are ACIS T_GAIN Epochs 77 + 78 (effective 01 Feb 2019 through 31 Jul 2019), HRC-S Version N0012 time-dependent QEU upgrade files, and HRC-I/S SAMP-based RMF files version N0002. See the CalDB 4.8.4 Release Notes for details.

23 May 2019

CalDB 4.8.3, an upgrade to CalDB 4.8.2 and later versions, has been released. Included items are ACIS T_GAIN Epochs 75 + 76 (effective 01 Aug 2018 through 31 Jan 2019), and HRC-S Version N0011 time-dependent QEU upgrade files. See the CalDB 4.8.3 Release Notes for details.

13 Dec 2018

CalDB 4.8.2, an upgrade to CalDB 4.8.2 and later versions, has been released. Included items are HRC-I 2018 GMAP (sampgain) upgrade with associated PIBGSPEC (background spectrum), and HRC-S Version N0010 time-dependent QEU upgrade files. See the CalDB 4.8.2 Release Notes for details.

13 Dec 2018

Chandra CfP Cycle 21 proposal planning support data and information have been released, including PIMMS Effective Areas, and model ARFs and RMFs for ACIS Imaging and GRATINGs proposal planning purposes. See the Calibration Proposal Planning web pages for information and access to downloadable files.

25 Oct 2018

CalDB 4.8.1, an upgrade to CalDB 4.7.3 and later versions, has been released. Included items are ACIS Contamination (CONTAM) file version N0012, with an upgrade to the ACIS-S model. See the CalDB 4.8.1 Release Notes for details.

11 Sep 2018

CalDB 4.8.0, an upgrade to CalDB 4.8.2 and later versions, has been released. Included items are ACIS time-dependent gain correction updates for Epochs 73 & 74 (01 Feb through 31 July 2018) and finalization of the Epochs 71 & 72 files (01 Aug 2017 through 31 Jan 2018.) See the CalDB 4.8.0 Release Notes for details.

28 Jun 2018

CalDB 4.7.9, an upgrade to CalDB 4.8.2 and later versions, has been released. Included items are ACIS CONTAM verion N0011, with modifications to the ACIS-I array, HRC-I time-dependent QE files, and HRC-S upgraded time-dependent QEU files. See the CalDB 4.7.9 Release Notes for details.

19 Mar 2018

CalDB 4.7.8, an upgrade to CalDB 4.7.3 and later versions, has been released. Included items are ACIS T_GAIN Epochs 71+72 (Aug 2017 through Jan 2018) updates, with final versions of Epochs 69+70 (Feb through Jul 2017), as well as an upgrade of the HRC-S GAPLOOKUP (degap solution) table to version N0004. See the CalDB 4.7.8 Release Notes for details.