eSASS calibration database (CALDB)

The Calibration Database (CALDB) of the eROSITA Science Analysis Software System (eSASS) stores and makes available files associated with the calibration of the eROSITA telescope. eSASS uses the HEASARC CALDB framework to manage the eROSITA calibration files. To download the eSASS CALDB, please refer to this page. To learn more about how a CALDB works, please visit the HEASARC CALDB site. The content of the eSASS CALDB is described in this webpage, but a detailed description of the CALDB can be found in the appendix B of Brunner, H., et al. (2022).

Organisation of the eSASS CALDB

• eROSITA has 7 telescope modules (TMs), and each one has its own set of calibration files.
• The calibration files of the individual TMs reside in separate directories: /<my CALDB path>/data/erosita/tm[1-7]/bcf/.
• Star sensors BOKZ, SED1 and SED2 have their own calibration file which are in their own directories: /<my CALDB path>/data/erosita/<starsensor>/bcf/.
• The gyro has its own calibration file in different versions for different time periods in directory: /<my CALDB path>/data/erosita/gyro/bcf/.
• A new version of an individual calibration file is created each time this calibration data is updated. There are two exceptions: tm<id>_timeoff_190701v<??>.fits and tm<id>_badcamt_190701v<??>.fits. The version number of these files is only incremented if an existing entry is changed. Adding a new entry does not change the version number. This is because otherwise, the large operational number of new entries would drive the version numbers up.
• A calibration index file (caldb.indx), which exists for each TM, each star sensor and gyro, manages which calibration files are currently in use and for which period. For this, each calibration file is assigned a quality flag: from 0 for good to 5 for bad (-1 reason for bad flag unknown, -9 dataset no longer exists). Old calibration files are usually kept in the respective */bcf/ directory. The individual caldb.indx is located in the directory above */bcf/.

Naming convention of the calibration files

 
      <instrume>_<name>[_<detnam>][_<filter>]_<startvalidity>v<nn>.fits


      instrume          content of the INSTRUME keyword in cal file 
                        eROSITA telescope modules: tm1... tm7

			
       name             type of calibration file from CCLS0001 keyword of cal file
                        e.g. 2dpsf for 2-dimensional point spread function.

       detnam, filter   if needed to distinguish between calibration datasets, 
                        optional keywords, may be used, e.g. to distinguish between the 'filter' 
                        and 'open' filter wheel positions.

       startvalidity    validity start date from CVSD0001 keyword in the form 'yymmdd'

       nn               version number
      
      

List of calibration files for star sensors

Calibration file	Task using the calibration file	Description
bokz_boresight_170630v03	attprep	Boresight quaternion of star sensor BOKZ on ART-XC.
sed1_boresight_170630v03	attprep	Boresight quaternion of star sensor SED1 on eROSITA.
sed2_boresight_170630v03	attprep	Boresight quaternion of star sensor SED2 on eROSITA.

List of calibration files for gyro

Calibration file	Task using the calibration file	Description
gyro_boresight_170630v04	attprep	Boresight quaternion of gyro from 30.06.2017 00:00 UTC on.
gyro_boresight_191131v07	attprep	Boresight quaternion of gyro from 30.11.2019 00:00 UTC on.
gyro_boresight_191208v10	attprep	Boresight quaternion of gyro from 08.12.2019 14:00 UTC on.
gyro_boresight_200611v11	attprep	Boresight quaternion of gyro from 11.06.2020 11:00 UTC on.

List of calibration files for TMs

Listed are the versions numbers of all calibration files which were used in the whole c010 processing not only DR1. Therefore the CALDB also contains files, which were not used for DR1, because their application is only necessary at a later date.

Calibration file	Version[1]	Task using the calibration file	Description
tm[1-7]_2dpsf_190220v03		erbox, ermldet, ersensmap, erbackmap, srctool	Survey-averaged and interpolated PANTER images; for detection (by erbox and ermldet, if used in image mode) and data modelling (a detailed description you can find here).
tm[1-7]_2dpsf_190219v05		erbox, ermldet, ersensmap, erbackmap, srctool	2D PSF images interpolated from PANTER; used for PSF correction (a detailed description you can find here).
tm[1-7]_arf_filter_000101v02		expmap, srctool	Predicted and approximated ARF.
tm[1-4,6]_arf_open_000101v02		expmap, srctool	Only for TMs with on-chip filter.
tm[1-7]_avignet_010101v01			eROSITA vignetting coefficients.
tm[1-7]_avignet2_010101v01		Obsolete: was used by srctool, expmap	Analytic vignetting cofficients for vignetting computation.
tm[1-7]_badcamt_190701v<??>	02/03/03/08/04/06/03	evprep	Time intervals for which no or corrupt data exists. In Cal-PV only used for TM3 and TM6 (each v01).
tm[1-7]_badpix_190712v<??>	-/01/-/-/-/01/01	expmap, srctool	Bright or flickering pixels or columns appearing after launch, used to account for lost area by bad pixels.
tm[1-7]_badpix_990101v<??>	01/-/01/01/01/-/-	expmap, srctool	empty file; only needed for the time period after launch if there are no bad pixels.
tm[2]_badpix_210117v01		expmap, srctool	Old and new bright or flickering pixels or columns appearing during flight, used to account for lost area by bad pixels.
tm[3]_badpix_201127v01		expmap, srctool	New bright or flickering pixels or columns appearing during flight, used to account for lost area by bad pixels.
tm[4]_badpix_191205v02		expmap, srctool	New bright or flickering pixels or columns appearing during flight, used to account for lost area by bad pixels.
tm[4]_badpix_210223v10			Old plus the new bright or flickering pixels or columns which appeared after the micrometeoroid impact, used to account for lost area by bad pixels.
tm[4]_badpix_210616v02
tm[4]_badpix_210805v03
tm[5]_badpix_210310v13		expmap, srctool	New bright or flickering pixels or columns, which appeared after the micrometeoroid impact, used to account for lost area by bad pixels.
tm[5]_badpix_210616v02
tm[6]_badpix_191023v01		expmap, srctool	Old and new bright or flickering pixels or columns appearing during flight, used to account for lost area by bad pixels.
tm[7]_badpix_210129v05		expmap, srctool	Old and the new bright or flickering pixels or columns, which appeared after the micrometeoroid impact, used to account for lost area by bad pixels.
tm[7]_badpix_210207v02
tm[7]_badpix_210210v02
tm[7]_badpix_210211v08
tm[7]_badpix_210616v02
tm[1-7]_corr_algos_190701v	-/-/-/-/02/-/02	evprep	Time intervals for which special corrections have to be applied; they are not included in the standard pipeline processing; not used in Cal-PV data.
tm[1-7]_detmap_100602v02		srctool, evprep, expmap	Detector map; same as fovmap but data format is real.
tm[1-7]_energy_190714v06		energy	Parameters for the CTI and gain correction.
tm[1-7]_fovmap_190822v01		expmap	Detector map; same as detmap, but integer data.
tm[1-7]_instpar_190701v15	Fixed to 15	apetool, evatt, expmap, srctool, tel, telatt	Detector geometry: focal length, platescale, number of pixels, boresight etc.; no information on time shifts which can be found in tm?_timeoff*
tm[1-5]_instpar_200212v<??[2]>	09/10-12/10/10-11/09-10	apetool, evatt, expmap, srctool, tel, telatt	Detector geometry: focal length, platescale, number of pixels, boresight etc.; with information on time shifts.
tm[6-7]_instpar_200213v<??[2]>	09/10	apetool, evatt, expmap, srctool, tel, telatt	Detector geometry: focal length, platescale, number of pixels, boresight etc.; with information on time shifts.
tm[1-7]_instpar_100705v<??[2]>	08/08/02/08/08/07/08	apetool, evatt, expmap, srctool, tel, telatt	Detector geometry with information on time shifts.
tm[1]_instpar_200331v10		apetool, evatt, expmap, srctool, tel, telatt	Detector geometry with information on time shifts for TM1.
tm[2]_instpar_191203v13		apetool, evatt, expmap, srctool, tel, telatt	Detector geometry with information on time shifts for TM2.
tm[3]_instpar_160523v09		apetool, evatt, expmap, srctool, tel, telatt	Detector geometry with information on time shifts for TM3.
tm[3]_instpar_200403v11
tm[3]_instpar_200509v12
tm[4]_instpar_191211v09		apetool, evatt, expmap, srctool, tel, telatt	Detector geometry with information on time shifts for TM4.
tm[5]_instpar_200506v11		apetool, evatt, expmap, srctool, tel, telatt	Detector geometry with information on time shifts for TM5.
tm[6]_instpar_200205v08		apetool, evatt, expmap, srctool, tel, telatt	Detector geometry with information on time shifts for TM6.
tm[6]_instpar_200213v09
tm[7]_instpar_200207v09		apetool, evatt, expmap, srctool, tel, telatt	Detector geometry with information on time shifts for TM7.
tm[1-7]_patfrac_140625v01		energy, srctool	Pattern fractions.
tm[1-7]_rmf_141103v01      tm[1-7]_rmf_141103v02		srctool	RMF derived from BESSY measurements.
tm[1-2]_slet_psf_171218v02		ermldet, shapelib	Shapelet PSF coefficients.
tm[3-7]_slet_psf_181217v02
tm[1-7]_subpix_130101v01		energy	Parameters for the subpixel calculation.
tm[1-7]_thr_191001v01		evprep	Threshold maps used by evprep before version 2.21.
tm[1-7]_thrscal_200119v01		evprep	Scaled threshold map suitable for evprep-2.21 and higher.
tm[1-7]_timeoff_190701v<??>	01/02/02/02/02/02/02	evprep	Time and date of time shift by 1 sec; there are only shifts between 0<->+1.
tm[1-7]_tvignet_100302v01		apetool	Total (mirror+obscuration) vignetting function.

[1] Only if individual TMs in c010 processing have different version numbers due to a different calibration history. Different versions are separated by "/". In case a calibration file does not exist for a TM it is marked by "-".

[2] Version number is always lower than 15. Since one instpar-file is needed for each event, there can be more than one version number for a TM.