NIR Calibrated Frame Catalog

Data product name

DpdNirCalibratedFrameCatalog

Data product custodian

NIR

Name of the Schema File

euc-nir-CalibratedFrameCatalog.xsd

Last Edited for DPDD Version

1.1

Processing Elements Creating / Updating / Using the Product

Creators:

Consumers:

Processing Function using the products

  • PF-NIR

Proposed for inclusion in EAS/SAS

This product is proposed for inclusion in the SAS: yes

This is one of the main PF-NIR products and it is the catalog extracted from fully calibrated NIR Calibrated Frame image.

Data Product Elements

Header:

object of type sys:genericHeader

Data:

object of type nir:nirCalibratedCatalog

QualityFlags:

object of type dqc:sqfPlaceHolder

Parameters:

object of type ppr:genericKeyValueParameters

Detailed Description of the Data Product

The DpdNirCalibratedFrameCatalog is the catalog extracted from the NIR Calibrated Frame.

../../_images/nirCalibratedCatalog.png

Fig. 22 : Graphical representaton of Data section structure for DpdNirCalibratedFrameCatalog

Main metadata stored into the Data structure are:

  • SpatialCoverage: the catalog sky coverage as polygon corners coordinates including the observation

  • SpectralCoverage: the filter list included into the catalog

  • CatalogDescription: a set of info to describe and identify catalog (i.e. origin, filepath)

  • ObservationId: the Observation ID

  • CalBlockId: the Calibration Block ID

  • CalBlockVariant: the Calibration Variant

  • DataStorage: the FITS file name

  • Instrument: Euclid Instrument

  • ObservationDateTime: Observation Date and Time

  • TargetPointing: Target Pointings Coordinates

  • DitherObservation: the Dither Observation

  • PhotometricCalibrated: Boolean value to identify if it is photometrically calibrated

  • QualityParams: list of Quality Parameters

As illustraded into the

Scientific FITS File

The catalog is stored in a FITS file which is linked in the Data.DataStorage metadata. The catalog is extracted from NIR Calibrated Frame and, therefore, its file structure reflects the origin FITS file.

It is then composed by a PRIMARY layer, with the main infomation on pointings, and other 16 layers, 1 layer for each detector, named DETxy.SCI` as in the NIR Calibrated Frame FITS file. These layers store a table with the extracted catalog for eahc detector.

The NIR_Catalog_Extraction task detects sources with a dedicated algorithm and, then, extracts source photometry (using SExtractor software) with 3 different methods: * MagAper: photometry with 6 pixels size aperture * MagAuto: as defined by SExtractor * MagPSF: a PSF fitting extraction performed by SExtractor

Primary layer

The FITS file has a PRIMARY header with main information on the pointing.

HDU PRIMARY: header

Name

Description

Value

Keywords

FITS_DEF

FITS name definition

string = nir.calCatalog

FITS_VER

FITS version

string = 0.3

ID_CATA

idCatalog = Catalog identifier

integer

RA_PNT

TargetPoiting:RA Center of field of view right ascension (deg)

double

DEC_PNT

TargetPoiting:DEC Center of field of view right declination (deg)

double

PA_PNT

TargetPoiting:PA Orientation of field of original view right (deg)

double

EXPTIME

ExposureTime Total integration time in seconds, e.g. 60.0005

double

TELESCOP

string = Euclid

FILTER

Filter Filter name, e.g. NIR_J

string

INSTRUME

or NISPsim for simulations

string = NISP

OBSMODE

eso:dataProduct:ThirdType DP type (WIDE, DEEP, CALIBRATION)

string

DATE-OBS

ObservationDateTime:OBT Date of observation (start), e.g. 2014-03-15T09:30:09.313

string

UTC-OBS

ObservationDateTime:UTC UTC time correlated to the on-board time by the Mission Operation Centre, e.g. 2014-03-15T09:30:09.313Z

string

MJD-OBS

ObservationDateTime:MJD MJD start time, e.g. 56731.39594113

double

OBS_ID

ObservationSequence:ObservationId Running Sequence number of the Observed block

integer

DITHOBS

ObservationSequence:DitherObservation Number sequence of dithering i.e. 1-4 for WIDE survey

integer

PTGID

eso:observationSequence:PointingID Integer number defining exposure inside observation

integer

EXPNUM

eso:observationSequence:Exposure Internal integer counter for single images

integer

TOTEXP

eso:observationSequence:TotalExposure Total number of Exposures in specific pointing

integer

PHOT_CAL

PhotometricCalibrated Boolean value to indicate if magnitudes are photometric calibrated or not

logical

DET_SIG

Detection threshold used during catalog extraction

double

From the corresponding calibrated frame are inherited the pointing coordinates and all the keywords needed to univocal identify the observation (i.e. Observation Id, Dither and Exposure number).

Scientific layer

The NIR_Catalog_Extraction task extracts a catalog from each detector.

Catalogs have the next columns:

Catalog: 44 columns table

Name

Description

Unit

Format

OBJECT_ID

Unique source identifier (MER tool)

NA

FITS K

XWIN_IMAGE

Windowed position estimate along x(XWIN_IMAGE)

pixel

FITS D

YWIN_IMAGE

Windowed position estimate along y (YWIN_IMAGE)

pixel

FITS D

XWIN_WORLD

Windowed position along world x axis (XWIN_WORLD)

deg

FITS D

YWIN_WORLD

Windowed position along world y axis (YWIN_WORLD)

deg

FITS D

ALPHA_J2000

Right ascension of barycenter (J2000) (Sextractor ALPHA_J2000)

deg

FITS D

DELTA_J2000

Declination of barycenter (J2000) (Sextractor DELTA_J2000)

deg

FITS D

MAG_APER

Fixed aperture magnitude vector (Sextractor MAG_APER)

mag

FITS E

MAGERR_APER

RMS error vector for fixed aperture mag (Sextractor MAGERR_APER)

mag

FITS E

FLUX_APER

Flux vector within fixed circular aperture (Sextractor FLUX_APER)

count

FITS E

FLUXERR_APER

RMS error vector for aperture flux (Sextractor FLUXERR_APER)

count

FITS E

MAG_AUTO

Kron-like elliptical aperture magnitude (Sextractor MAG_AUTO)

mag

FITS E

MAGERR_AUTO

RMS error for AUTO magnitude (Sextractor MAGERR_AUTO)

mag

FITS E

FLUX_AUTO

Flux within a Kron-like elliptical aperture (Sextractor FLUX_AUTO)

count

FITS E

FLUXERR_AUTO

RMS error for AUTO flux (Sextractor FLUXERR_AUTO)

count

FITS E

AWIN_WORLD

Windowed profile RMS along major axis (Sextractor AWIN_WORLD)

deg

FITS E

BWIN_WORLD

Windowed profile RMS along minor axis (Sextractor BWIN_WORLD)

deg

FITS E

THETAWIN_WORLD

Windowed position angle (CCW/world-x) (Sextractor THETAWIN_WORLD)

deg

FITS E

ERRAWIN_WORLD

SWorld RMS windowed pos error along major axis (Sextractor ERRAWIN_WORLD)

deg

FITS E

ERRBWIN_WORLD

World RMS windowed pos error along minor axis (Sextractor ERRBWIN_WORLD)

deg

FITS E

ERRTHETAWIN_WORLD

Windowed error ellipse pos. angle (CCW/world-x) (Sextractor ERRTHETAWIN_WORLD)

deg

FITS E

KRON_RADIUS

Kron apertures in units of A or B (Sextractor KRON_RADIUS)

deg

FITS D

ELLIPTICITY

Source ELLIPTICITY shape parameter. 1 - B_IMAGE/A_IMAGE(Sextractor ELLIPTICITY)

NA

FITS D

CLASS_STAR

Source star class shape parameter. S/G classifier output (Sextractor CLASS_STAR)

NA

FITS E

SPREAD_MODEL

Spread parameter from model-fitting (Sextractor SPREAD_MODEL)

NA

FITS E

FWHM_IMAGE

FWHM assuming a gaussian core (Sextractor FWHM_IMAGE)

pixel

FITS E

FLUX_RADIUS

Fraction-of-light radii (Sextractor FLUX_RADIUS)

count

FITS E

BACKGROUND

Background at centroid position (Sextractor BACKGROUND)

ADU

FITS D

THRESHOLD

Detection threshold about background (Sextractor THRESHOLD)

NA

FITS D

XPSF_IMAGE

X coordinate from PSF-fitting (XPSF_IMAGE)

pixel

FITS D

YPSF_IMAGE

Y coordinate from PSF-fitting (YPSF_IMAGE)

pixel

FITS D

XPSF_WORLD

PSF position along world x axis (XPSF_WORLD)

deg

FITS D

YPSF_WORLD

PSF position along world y axis (YPSF_WORLD)

deg

FITS D

ALPHAPSF_J2000

Right ascension of the fitted PSF (J2000) (Sextractor ALPHAPSF_J2000)

deg

FITS D

DELTAPSF_J2000

Declination of the fitted PSF (J2000) (Sextractor ALPHAPSF_J2000)

deg

FITS D

MAG_PSF

Magnitude from PSF-fitting (Sextractor MAG_PSF)

mag

FITS E

MAGERR_PSF

RMS magnitude error from PSF-fitting (Sextractor MAGERR_PSF)

mag

FITS E

FLUX_PSF

Flux from PSF-fitting (Sextractor FLUX_PSF)

count

FITS E

FLUXERR_PSF

RMS flux error for PSF-fitting (Sextractor FLUXERR_PSF)

count

FITS E

ERRAPSF_IMAGE

PSF RMS position error along major axis (Sextractor ERRAPSF_IMAGE)

pixel

FITS E

ERRBPSF_IMAGE

PSF RMS position error along minor axis (Sextractor ERRBPSF_IMAGE)

pixel

FITS E

ERRTHETAPSF_IMAGE

PSF error ellipse position angle (CCW/x) (Sextractor ERRTHETAPSF_IMAGE)

deg

FITS E

CHI2_PSF

Reduced chi2 from PSF-fitting (Sextractor CHI2_PSF)

NA

FITS E

FLAGS

SExtractor Extraction flags (Sextractor FLAGS)

NA

FITS I

where are reported all the 3 photometies with the corresponding uncertaintains.

Quality Parameters

A very usefull section it could be the Data.QualityParams, here represented

../../_images/nirCalibratedCatalog_dqc.png

Fig. 23 : Graphical representaton of Data.QualityParams section structure for the DpdNirCalibratedFrameCatalog

It cointains some very useful information to describe the catalog content and verify its quality.

  • ObjectCount is the total number of sources

  • sections MagAper, MagAuto and MagPSF contain statistics on photometric measures obtained with the 3 different methods

  • sections Bright and Faint list statistics on photometric errors from the 3 extraction methods for the brighter and fainter part of the catalog.