Shear PSF Model Image

Data product name

shePsfModelImage

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 shePsfModelImage:

This product contains the postage stamps for the PSF of the object. It has a FITS product with 3 HDUs, one containing the postage stamp of the bulge, one the postage stamp of the disk and one for a catalogue of the position, calibration and field parameters

Documentation for data product element Header:

The generic header of the product.

Data product elements

  • DataStorage (shePsfModelImageFile)

  • DataContainer (dss:dataContainer)

  • ExposureProductId (string)

  • ObservationId (long)

Processing Element(s) creating/using the data product

SHE_PSFToolkit

Processing function using the data product

SHE

Detailed description of the data product

Data product containing a per-object broadband PSF, as output of the SHE_PSFToolkit software, for a catalogue of sources.

Stores each PSF image as a FITS file containing 3 HDUs NxN array (size set by user on runtime), as well as meta-data linking to object in question. The FITS file is in an XML container, which also stores the ExposureProductID and ObservationID linking to the VIS input file that the postage stamp is created from. The pixel size is set by the user.

The FITS output file will contain the following information:

HDUs

  1. “Primary”: Header only HDU

#. “PSFC”: Catalogue containing additional information for PSF determination for object For each PSF defined in the PSFC there are the following HDUs #. “BPSF”: Bulge PSF images (as postage stamps) #. “DPSF”: Disk PSF images (as postage stamps)

Primary

Header +————–+———–+——–+—————————–+ | Keyword name | Optional? | Format | Brief description | +==============+===========+========+=============================+ | FITS_VER | No | String | Table format version number | +————–+———–+——–+—————————–+ | FITS_DEF | No | String | Table format label | +————–+———–+——–+—————————–+ | EQUINOX | No | Double | | +————–+———–+——–+—————————–+ | MJD-OBS | No | Double | | +————–+———–+——–+—————————–+ | RADESYS | No | String | | +————–+———–+——–+—————————–+ | CTYPE1 | No | String | | +————–+———–+——–+—————————–+ | CUNIT1 | No | String | | +————–+———–+——–+—————————–+ | CRVAL1 | No | Double | | +————–+———–+——–+—————————–+ | CRPIX1 | No | Double | | +————–+———–+——–+—————————–+ | CD1_1 | No | Double | | +————–+———–+——–+—————————–+ | CD1_2 | No | Double | | +————–+———–+——–+—————————–+ | CTYPE2 | No | String | | +————–+———–+——–+—————————–+ | CUNIT2 | No | String | | +————–+———–+——–+—————————–+ | CRVAL2 | No | Double | | +————–+———–+——–+—————————–+ | CRPIX2 | No | Double | | +————–+———–+——–+—————————–+ | CD2_1 | No | Double | | +————–+———–+——–+—————————–+ | CD2_2 | No | Double | | +————–+———–+——–+—————————–+

PSFC

Header +————–+———–+——–+————————————————————-+ | Keyword name | Optional? | Format | Brief description | +==============+===========+========+=============================================================+ | FITS_VER | No | String | Table format version number | +————–+———–+——–+————————————————————-+ | FITS_DEF | No | String | Table format label | +————–+———–+——–+————————————————————-+ | CAL_PROD | No | String | ProductId identifying the PSF calibration data product used | +————–+———–+——–+————————————————————-+ | CAL_TIME | No | String | Timestamp identifying the PSF calibration data product used | +————–+———–+——–+————————————————————-+ | FLD_TIME | No | String | Timestamp identifying the PSF field data product used | +————–+———–+——–+————————————————————-+ | FLD_PROD | No | String | ProductId identifying the PSF field data product used | +————–+———–+——–+————————————————————-+

Data

Catalogue connecting PSF image information to requested objects.

Table will include the following columns: +————————–+—————-+———————————————————————————-+ | Parameter name | Fits Data type | Brief description | +==========================+================+==================================================================================+ |OBJECT_ID | K | Identifier for object for which PSF was requested | +--------------------------+----------------+----------------------------------------------------------------------------------+ |SHE_PSF_SED_TEMPLATE | K | Identifiers for templates used in construction of the PSF | +--------------------------+----------------+----------------------------------------------------------------------------------+ |SHE_PSF_BULGE_IDX | J | HDU index of the Bulge PSF | +--------------------------+----------------+----------------------------------------------------------------------------------+ |SHE_PSF_DISK_IDX | J | HDU index of the Disk PSF | +--------------------------+----------------+----------------------------------------------------------------------------------+ |SHE_PSF_IMAGE_X | I | X co-ordinate of the postage stamp on the exposure | +--------------------------+----------------+----------------------------------------------------------------------------------+ |SHE_PSF_IMAGE_Y | I | Y co-ordinate of the postage stamp on the exposure | +--------------------------+----------------+----------------------------------------------------------------------------------+ |SHE_PSF_X | E | X co-ordinate of the centre of the PSF on the postage stamp (includes sub pixel) | +--------------------------+----------------+----------------------------------------------------------------------------------+ |SHE_PSF_Y | E | Y co-ordinate of the centre of the PSF on the postage stamp (includes sub pixel) | +--------------------------+----------------+----------------------------------------------------------------------------------+ |SHE_PSF_CALIB_TIME | 20A | Timestamp identifying the PSF calibration data product used | +--------------------------+----------------+----------------------------------------------------------------------------------+ |SHE_PSF_FIELD_TIME | 20A | Timestamp identifying the PSF field param data product used | +--------------------------+----------------+----------------------------------------------------------------------------------+ |SHE_PSF_QUAL_FLAG | J | Quality flag of PSF model fit. | +--------------------------+----------------+----------------------------------------------------------------------------------+ |SHE_PSF_CHI1_IMAGE | E | First moment of PSF ellipticity (chi, see 1 below) in x-image coordinate / pixels| +————————–+—————-+———————————————————————————-+ |SHE_PSF_CHI2_IMAGE | E | First moment of PSF ellipticity (chi, see 1 below) in y-image coordinate / pixels| +————————–+—————-+———————————————————————————-+ |SHE_PSF_R2 | E | Quadrupole (Mxx+Myy) moment measure of PSF area / arcsec^2 | +————————–+—————-+———————————————————————————-+ |SHE_PSF_STREHL | E | Strehl ratio of PSF | +————————–+—————-+———————————————————————————-+ |SHE_PSF_CHI1_IMAGE_ERR | E | Error on first moment of PSF ellipticity in x-image coordinate / pixels (see 2) | +————————–+—————-+———————————————————————————-+ |SHE_PSF_CHI2_IMAGE_ERR | E | Error on first moment of PSF ellipticity in y-image coordinate / pixels (see 2) | +————————–+—————-+———————————————————————————-+ |SHE_PSF_R2_ERR | E | Error on quadrupole moment measure of PSF area / arcsec^2 (see 2 below) | +————————–+—————-+———————————————————————————-+

Notes:
  • 1 chi = (1-r^2)/(1+r^2) is the definition of ellipticity from shear measurement

  • 2 When errors cannot be reasonably calculated, the value should be NaN

BPSF

(Postage Stamp) Image of PSF for bulge of object.

Header +————–+———–+———+—————————–+ | Keyword name | Optional? | Format | Brief description | +==============+===========+=========+=============================+ | FITS_VER | No | String | Table format version number | +————–+———–+———+—————————–+ | FITS_DEF | No | String | Table format label | +————–+———–+———+—————————–+ | BITPIX | No | Integer | | +————–+———–+———+—————————–+ | NAXIS | No | Integer | | +————–+———–+———+—————————–+ | NAXIS1 | No | Integer | | +————–+———–+———+—————————–+ | NAXIS2 | No | Integer | | +————–+———–+———+—————————–+ | EXTEND | No | Logical | | +————–+———–+———+—————————–+ | PIXSCALE | No | Double | | +————–+———–+———+—————————–+

Data

Data will contain an NxN image (size TBF) of floats, representing the PSF for the bulge of the object.

WcsList List of WCS RA, DEC for each WCS used.

DPSF

As BPSF, for the disk of the object.