QSO candidates (gaiadr3.qso_candidates)

The table has 6649162 rows, 41 columns.

Description

This table contains parameters derived from various modules dedicated to the classification and characterisation of sources considered as QSO candidates. Together with those, the QSOs used to define the Gaia-CRF3 are also listed in this table. This table has been constructed with the intention to be complete rather than pure and, as such, it will contain a large fraction of non-genuine extragalactic sources. Purer samples can be drawn using dedicated flags or queries. Please refer to Chapter cu3qso of the on-line documentation for details about how this table was built, its content, and for recommendations regarding its exploitation.

Known issues

The surface brightness sample published in the qso_candidates is based on an input list of sources described in Section 9.2 of the on-line documentation. This list was built based on external catalogues and the table qso_catalogue_name provides the names of the applicable catalogues for each of the sources featuring surface brightness parameters in qso_candidates. Due to an oversight during the processing, the catalogue name is missing for 494 sources. In this file, the list of affected sourceIds is provided.

Attribution

If you have used Gaia data in your research, please use the following acknowledgement:

This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement.

More information can be found on the credit and citation instructions page.

Columns

Name Type UCD Unit Description
solution_id long meta.version

Solution Identifier
source_id long meta.id
meta.main
meta.ref

Unique source identifier (unique within a particular Data Release)
astrometric_selection_flag boolean meta.code.status

Flag indicating if the source is part of the astrometric selection
gaia_crf_source boolean meta.code.status

Flag indicative of whether the source was used define the Gaia-CRF3
vari_best_class_name char meta.code.class

Name of best class, see table VariClassifierClassDefinition for details of the class
vari_best_class_score float stat.probability

Score of the best class
fractional_variability_g float src.var.amplitude
em.opt

Fractional variability in the G band
structure_function_index float src.var.index

Index of the first-order structure function in the G band
structure_function_index_scatter double stat.stdev

Standard deviation of the index of the structure function
qso_variability float src.var

Quasar variability metric in the G band
non_qso_variability float src.var

Non-quasar variability metric in the G band
vari_agn_membership_score double stat.probability

Membership score (0=lowest,1=highest) of source to be of AGN type
classprob_dsc_combmod_quasar float stat.probability

Probability from DSC-Combmod of being a quasar (data used: BP/RP spectrum, photometry, astrometry)
classprob_dsc_combmod_galaxy float stat.probability

Probability from DSC-Combmod of being a galaxy (data used: BP/RP spectrum, photometry, astrometry)
classlabel_dsc char meta.code.class

Class assigned by DSC based on the probability from its Combmod classifier
classlabel_dsc_joint char meta.code.class

Class assigned by DSC based on the probability from its Specmod and Allosmod classifiers
classlabel_oa char meta.code.class

Class assigned by OA the neuron that represents the source
redshift_qsoc float src.redshift

Redshift from QSOC
redshift_qsoc_lower float stat.value
src.redshift

Redshift lower confidence level from QSOC
redshift_qsoc_upper float stat.value
src.redshift

Redshift upper confidence level from QSOC
ccfratio_qsoc float stat.value

Value of the cross-correlation function used to derive the redshift from QSOC, relative to the maximum value
zscore_qsoc float stat.value
src.redshift

Redshift zscore from QSOC
flags_qsoc long meta.code.status

Processing flags for the analysis based on BP/RP Spectra from QSOC
n_transits integer meta.number

Number of transits used for the morphological analysis
intensity_quasar double phot.flux
em.opt 		"electron".s**-1

Fitted intensity of the quasar at its center
intensity_quasar_error double stat.error
phot.flux
em.opt 		"electron".s**-1

Error on the fitted intensity of the quasar at its center
intensity_hostgalaxy double phot.flux
em.opt 		"electron".s**-1

Fitted intensity of the host galaxy at the effective radius
intensity_hostgalaxy_error double stat.error
phot.flux
em.opt 		"electron".s**-1

Error on the fitted intensity of the host galaxy at effective radius
radius_hostgalaxy double src.morph.param mas

Fitted effective radius of the host galaxy
radius_hostgalaxy_error double stat.error mas

Error on the fitted effective radius of the host galaxy
sersic_index float src.morph.param

Fitted sersic Index
sersic_index_error float stat.error

Error on the fitted sersic Index
ellipticity_hostgalaxy double src.ellipticity

Fitted ellipticity of the host galaxy
ellipticity_hostgalaxy_error double stat.error
src.ellipticity

Error on the fitted ellipticity of the host galaxy
posangle_hostgalaxy double pos.posAng deg

Fitted position angle of the host galaxy
posangle_hostgalaxy_error double stat.error
pos.posAng 		deg

Error on the fitted position angle of the host galaxy
host_galaxy_detected boolean stat.fit.param

Flag indicating whether a host galaxy has been detected
l2_norm double stat.fit.param

L2 norm for the fitted Sersic profile
morph_params_corr_vec double[] stat.correlation

Vector form of the upper triangle of the correlation matrix for the fitted morphological parameters
host_galaxy_flag short meta.code.qual

Flag indicative of processing or scientific quality for the morphological parameters fitting
source_selection_flags integer meta.code.status

Bit indicative of whether the input data from a given module met the source list eligibility criteria for the source of interest