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Glossary of WSA NonSurvey attributes (UKIDSSR2)
This Glossary alphabetically lists all attributes used in the WSA NonSurvey database(s) held in the WSA. If you would like to have more information about the schema tables please use the Schema Browser (other Browser versions).

A

B

C

D

E

F

G

H

I

J

K

L

M

N

O

P

Q

R

S

T

U

V

W

X

Y

Z

K
Name	Schema Table	Database	Description	Type	Length	Unit	Default Value	Unified Content Descriptor
kAperMag3	[nspid]Source	WSA NonSurvey	Extended source K mag (2.0 arcsec aperture diameter)	real	4	mag	-0.9999995e9	PHOT_MAG
kAperMag3Err	[nspid]Source	WSA NonSurvey	Error in extended source K mag (2.0 arcsec aperture diameter)	real	4	mag	-0.9999995e9	ERROR
kAperMag4	[nspid]Source	WSA NonSurvey	Extended source K mag (2.8 arcsec aperture diameter)	real	4	mag	-0.9999995e9	PHOT_MAG
kAperMag4Err	[nspid]Source	WSA NonSurvey	Error in extended source K mag (2.8 arcsec aperture diameter)	real	4	mag	-0.9999995e9	ERROR
kAperMag6	[nspid]Source	WSA NonSurvey	Extended source K mag (5.7 arcsec aperture diameter)	real	4	mag	-0.9999995e9	PHOT_MAG
kAperMag6Err	[nspid]Source	WSA NonSurvey	Error in extended source K mag (5.7 arcsec aperture diameter)	real	4	mag	-0.9999995e9	ERROR
kClass	[nspid]Source	WSA NonSurvey	discrete image classification flag in K	smallint	2		-9999	CLASS_MISC
kClassStat	[nspid]Source	WSA NonSurvey	N(0,1) stellarness-of-profile statistic in K	real	4		-0.9999995e9	STAT_PROP
kDeblend	[nspid]Source	WSA NonSurvey	flag indicating parent/child relation in K	int	4		-99999999	CODE_MISC
kEll	[nspid]Source	WSA NonSurvey	1-b/a, where a/b=semi-major/minor axes in K	real	4		-0.9999995e9	PHYS_ELLIPTICITY
keNum	[nspid]MergeLog	WSA NonSurvey	the extension number of this K detector	tinyint	1			NUMBER
kErrBits	[nspid]Source	WSA NonSurvey	processing warning/error bitwise flags in K	int	4		-99999999	CODE_MISC
kEta	[nspid]Source	WSA NonSurvey	Offset of K detection from master position (+north/-south)	real	4	arcsec	-0.9999995e9	POS_EQ_DEC_OFF
			When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of typically 5 arcseconds is used, enabling pairing of moving sources when epoch separations may be several years. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs, you might wish to insist that the offsets in the selected sample are all below 1 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want.
kGausig	[nspid]Source	WSA NonSurvey	RMS of axes of ellipse fit in K	real	4	pixels	-0.9999995e9	MORPH_PARAM
kHallMag	[nspid]Source	WSA NonSurvey	Point source K mag	real	4	mag	-0.9999995e9	PHOT_MAG
kHallMagErr	[nspid]Source	WSA NonSurvey	Error in point source K mag	real	4	mag	-0.9999995e9	ERROR
kmfID	[nspid]MergeLog	WSA NonSurvey	the UID of the relevant K multiframe	bigint	8			ID_FRAME
kmh2Ext	[nspid]Source	WSA NonSurvey	Extended source colour K-H2	real	4	mag	-0.9999995e9	PHOT_COLOR
			Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours are computed from the seeing-matched aperture measure (the "Hall" magnitude) while the extended source colours are computed from the fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands). At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
kmh2ExtErr	[nspid]Source	WSA NonSurvey	Error on extended source colour K-H2	real	4	mag	-0.9999995e9	ERROR
			Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours are computed from the seeing-matched aperture measure (the "Hall" magnitude) while the extended source colours are computed from the fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands). At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
kmh2Pnt	[nspid]Source	WSA NonSurvey	Point source colour K-H2	real	4	mag	-0.9999995e9	PHOT_COLOR
			Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours are computed from the seeing-matched aperture measure (the "Hall" magnitude) while the extended source colours are computed from the fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands). At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
kmh2PntErr	[nspid]Source	WSA NonSurvey	Error on point source colour K-H2	real	4	mag	-0.9999995e9	ERROR
			Default colours from pairs of adjacent passbands within a given set (e.g. Y-J, J-H and H-K for YJHK) are recorded in the merged source table for ease of querying and speedy querying via indexing of these attributes. Presently, the point-source colours are computed from the seeing-matched aperture measure (the "Hall" magnitude) while the extended source colours are computed from the fixed 2 arcsec aperture diameter measures (for consistent measurement across all passbands). At some point in the future, this may be changed such that point-source colours will be computed from the PSF-fitted measures and extended source colours computed from the 2-d Sersic model profile fits.
kObjID	[nspid]Source	WSA NonSurvey	the UID of the K detection	bigint	8		-99999999	ID_NUMBER
kPA	[nspid]Source	WSA NonSurvey	ellipse fit celestial orientation in K	real	4	Degrees	-0.9999995e9	POS_POS-ANG
kPetroMag	[nspid]Source	WSA NonSurvey	Extended source K mag (Petrosian)	real	4	mag	-0.9999995e9	PHOT_MAG
kPetroMagErr	[nspid]Source	WSA NonSurvey	Error in extended source K mag (Petrosian)	real	4	mag	-0.9999995e9	ERROR
kppErrBits	[nspid]Source	WSA NonSurvey	additional WFAU post-processing error bits in K	int	4		-99999999	CODE_MISC
kPsfMag	[nspid]Source	WSA NonSurvey	Point source profile-fitted K mag	real	4	mag	-0.9999995e9	PHOT_MAG
kPsfMagErr	[nspid]Source	WSA NonSurvey	Error in point source profile-fitted K mag	real	4	mag	-0.9999995e9	ERROR
kronFlux	[nspid]Detection	WSA NonSurvey	flux within circular aperture to k × r_k ; k = 2 {catalogue TType keyword: Kron_flux}	real	4	ADU		PHOT_INTENSITY_ADU
kronFluxErr	[nspid]Detection	WSA NonSurvey	error on Kron flux {catalogue TType keyword: Kron_flux_err}	real	4	ADU		ERROR
kronMag	[nspid]Detection	WSA NonSurvey	Calibrated Kron magnitude within circular aperture r_k	real	4	mag		PHOT_INT-MAG
kronMagErr	[nspid]Detection	WSA NonSurvey	error on calibrated Kron magnitude	real	4	mag		ERROR
kronRad	[nspid]Detection	WSA NonSurvey	r_k as defined in Bertin and Arnouts 1996 A&A Supp 117 393 {catalogue TType keyword: Kron_radius}	real	4	pixels		EXTENSION_RAD
kSeqNum	[nspid]Source	WSA NonSurvey	the running number of the K detection	int	4		-99999999	ID_NUMBER
kSerMag2D	[nspid]Source	WSA NonSurvey	Extended source K mag (profile-fitted)	real	4	mag	-0.9999995e9	PHOT_MAG
kSerMag2DErr	[nspid]Source	WSA NonSurvey	Error in extended source K mag (profile-fitted)	real	4	mag	-0.9999995e9	ERROR
kXi	[nspid]Source	WSA NonSurvey	Offset of K detection from master position (+east/-west)	real	4	arcsec	-0.9999995e9	POS_EQ_RA_OFF
			When associating individual passband detections into merged sources, a generous (in terms of the positional uncertainties) pairing radius of typically 5 arcseconds is used, enabling pairing of moving sources when epoch separations may be several years. Such a large association criterion can of course lead to spurious pairings in the merged sources lists (although note that between passband pairs, handshake pairing is done: both passbands must agree that the candidate pair is their nearest neighbour for the pair to propagate through into the merged source table). In order to help filter spurious pairings out, and assuming that large positional offsets between the different passband detections are not expected (e.g. because of source motion, or larger than usual positional uncertainties) then the attributes Xi and Eta can be used to filter any pairings with suspiciously large offsets in one or more bands. For example, for a clean sample of QSOs, you might wish to insist that the offsets in the selected sample are all below 1 arcsecond: simply add WHERE clauses into the SQL sample selection script to exclude all Xi and Eta values larger than the threshold you want.