Shear KSB Calibration¶
Data product name¶
sheKsbCalibration
Data product custodian¶
SHE
Data model tag¶
8.0
Name of the Schema file¶
ST_DM_Schema/dictionary/pro/she/euc-test-she.xsd
Schema documentation tag¶
Documentation for data product element sheKsbCalibration:
This product contains the required calibration data for the KSB shear estimation method.
Documentation for data product element Header:
The generic header of the product.
Data product elements¶
ValidityRange (ins:calibrationValidPeriod)
KsbCalibrationFileList (sheKsbCalibrationFileList) [0+ elements]
KsbCalibrationFile 1
DataStorage (sheKsbCalibrationFile)
DataContainer (dss:dataContainer)
KsbCalibrationFile 2
DataStorage (sheKsbCalibrationFile)
DataContainer (dss:dataContainer)
…
Processing Element(s) creating/using the data product¶
SHE
Processing function using the data product¶
SHE
Detailed description of the data product¶
An XML data product containing calibration data for the KSB shear measurement algorithm. This algorithm requires priors on the unlensed shapes of galaxies in order to properly estimate errors, and so the calibration data is generated by running the KSB algorithm on a reference set of deep images with minimal noise. The resulting shape measurements are stored as the calibration data in a fits table with the following columns:
Parameter name |
Fits Data type |
Brief description |
|---|---|---|
OBJECT_ID |
K |
ID of the galaxy in the reference |
SHE_KSB_TRAINING_E1 |
E |
Measurement of first component of ellipticity |
SHE_KSB_TRAINING_E2 |
E |
Measurement of second component of ellipticity |
SHE_KSB_TRAINING_E1_ERR |
E |
Error on measurement of first component of ellipticity |
SHE_KSB_TRAINING_E2_ERR |
E |
Error on measurement of second component of ellipticity |
The distinction we use betwee “Training” and “Calibration” data is that Training data is data which can be obtained prior to any observations from Euclid (e.g. from Euclidized HST images), while Calibration data is obtained and updated throughout the Euclid mission.