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Directory Structure

The directory structure itself is determined by the keyword conventions, while the location of a given file within the CALDB is determined by its header keyword values. The CALDB directory structure is given in Table 1, which may be used to locate a specific file in your local CALDB.

**Table 1: Directory structure of the Chandra CALDB.**
TELESCOP	INSTRUME	INDEX/CCLS	CCNM
$CALDB/data/chandra/	acis/	index/	(ACIS index files)
		bcf/	badpix, evtsplt, gain, gtilim, grade, qe
		cpf/	2dpsf, fefs, osip
	ephin/	index/	(EPHIN index files)
		bcf/	geom
	hrc/	index/	(HRC index files)
		bcf/	badpix, degap, fptest, eftest, gtilim, sattest, tapring, qe
		cpf/	2dpsf
	pcad/	index/	(PCAD index files)
		bcf/	align, badpix, ccd, cti, fdc, image, iru, rws, sfma
	sim/	index/	(SIM index files)
		bcf/	pos, poscorr
	tel/	index/	(TEL index files)
		bcf/	aimpts, geom, sky, tdet, obitol
		DETNAM (INSTRUME="TEL")	CCLS (GRATING="NONE")	CCNM
		hrma/	bcf/	effarea, vignet
			cpf/	rpsf, wpsf
			GRATING	CCLS	CCNM
		grating/	hetg/	bcf/	greff
				cpf/	arf, rmf
			letg/	bcf/	greff
				cpf/	arf, rmf

The structure under the "tel" branch is dictated by the guidelines in the ASC FITS Designer's Guide (PS, 40pp). The GRATING keyword and a corresponding classification keyword in the index file are both required.

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.