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 4.9.2.1 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

14 Jul 2020 [New]

A revised version of the CalDB 4.9.2.1 upgrade file has been released to correct a potential unpacking issue some users were experiencing. See the Special Notice on Download CalDB 4.9.2.1 to determine if your installation has been affected.

09 Jul 2020 [New]

CalDB 4.9.2.1 has been released. Included in this release are (1) A full upgrade of the T_GAIN library (Epochs 1-80); (2) Extended ACIS FP_TEMP boundary conditions for warmer OBS_IDs; (3) HRC-S time-dependent gain maps V3; (4) HRC-S QE version N0015 time-displaced file set; (5)HRC-I QE version N0012 time-displaced file set. See the CalDB 4.9.2.1 Release Notes and the CalDB 4.9.2 Release Notes for details.

04 Apr 2020

CalDB 4.9.1 has been released. CalDB 4.9.2.1 is compatible only with CIAO 4.12, and vice versa! Included in this release are (1) ACIS T_GAIN updates for 02 May 2019 - present; (2) ACIS DET_GAIN/P2_RESP N0008 files to fix the FI mid-chip gain droop; (3) HRC-S QEU version N0013 file set; (4) ASPECT CALFDC N0004 with STAR and FID light plate scale upgrades. See the CalDB 4.9.2.1 Release Notes for details.

17 Dec 2019

CalDB 4.9.0 has been released. CalDB 4.9.2.1 is compatible only with CIAO 4.12, and vice versa! Included is an upgrade to the ACIS CalDB bad pixel library, to identify and tag events falling in the ACIS framestore shadow regions as bad pixel events, to be excluded in Level 2 filtering. This applies only to non-CC-mode observations at this point. See the CalDB 4.9.0 Release Notes for details.

17 Dec 2019

Chandra CfP Cycle 22 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.

07 Nov 2019

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.