TABLE  Detection

Each scanned plate in the SSA results in a pixel map. This map was processed using standard software (known as Image Analysis Mode, or IAM, software) to produce a list of parameterised detections on each plate. This table contains all the attributes for each detected object. The attribute set consists of the standard 32 IAM parameters plus calibrated photometry and spatial index quantities.

Name	Type	Length	Unit	Description	Default Value	Unified Content Descriptor
objID	bigint	8		Unique object identification number		ID_MAIN
surveyID	tinyint	1		The survey that collected the data		ID_SURVEY
plateID	int	4		Plate ID of the plate that this detection came from		ID_PLATE
parentID	bigint	8		objID of parent object, = objID for parent/undeblended (ie. not child) object		ID_PARENT
sourceID	bigint	8		objID for corresponding merged record in Source		ID_ASSOCIATED
recNum	int	4		The record number in the original IAM file		RECORD
ra	float	8	degrees	Celestial Right Ascension		POS_EQ_RA_MAIN
dec	float	8	degrees	Celestial Declination		POS_EQ_DEC_MAIN
htmId	bigint	8		Hierarchical Triangular Mesh (20-deep) of centroid		POS_GENERAL
cx	float	8		Cartesian x of unit (ra,dec) vector on celestial sphere		POS_EQ_X
cy	float	8		Cartesian y of unit (ra,dec) vector on celestial sphere		POS_EQ_Y
cz	float	8		Cartesian z of unit (ra,dec) vector on celestial sphere		POS_EQ_Z
xmin	float	8	microns	Leftmost extent of image on plate		POS_PLATE_X
xmax	float	8	microns	Rightmost extent of image on plate		POS_PLATE_X
ymin	float	8	microns	Bottommost extent of image on plate		POS_PLATE_Y
ymax	float	8	microns	Topmost extent of image on plate		POS_PLATE_Y
area	int	4	pixels	Area within detection isophote		EXTENSION_AREA
ipeak	real	4	instrumental units	Intensity of brightest pixel above sky		PHOT_INTENSITY_MISC
cosmag	real	4	instrumental units	Isophotal magnitude		PHOT_PHG_MAG
isky	real	4		Estimate of sky intensity at (xCen, yCen)		PHOT_SB_SKY
xCen	float	8	microns	Intensity-weighted X-centroid of image		POS_PLATE_X
yCen	float	8	microns	Intensity-weighted Y-centroid of image		POS_PLATE_Y
aU	real	4	microns	Semi-major axis of unweighted fitted ellipse		EXTENSION_RAD
bU	real	4	microns	Semi-minor axis of unweighted fitted ellipse		EXTENSION_SMIN
thetaU	smallint	2	degrees	Position angle (wrt x-axis) of unweighted fitted ellipse		POS_POS-ANG
aI	real	4	microns	Semi-major axis of intensity-weighted fitted ellip.		EXTENSION_RAD
bI	real	4	microns	Semi-minor axis of intensity-weighted fitted ellip.		EXTENSION_SMIN
thetaI	smallint	2	degrees	Position angle (wrt x-axis) of intensity-weighted fitted ellipse		POS_POS-ANG
class	tinyint	1		Classification flag		CLASS_OBJECT
pa	smallint	2	degrees	Celestial position angle (E of N)		POS_POS-ANG
ap1	int	4	pixels	Area above 1st areal profile threshold		EXTENSION_AREA
ap2	int	4	pixels	Area above 2nd areal profile threshold		EXTENSION_AREA
ap3	int	4	pixels	Area above 3rd areal profile threshold		EXTENSION_AREA
ap4	int	4	pixels	Area above 4th areal profile threshold		EXTENSION_AREA
ap5	int	4	pixels	Area above 5th areal profile threshold		EXTENSION_AREA
ap6	int	4	pixels	Area above 6th areal profile threshold		EXTENSION_AREA
ap7	int	4	pixels	Area above 7th areal profile threshold		EXTENSION_AREA
ap8	int	4	pixels	Area above 8th areal profile threshold		EXTENSION_AREA
blend	int	4		Deblend flag: -n=parent of n children; +n = nth child of a parent		CODE_MULT_INDEX
quality	int	4		Bitwise quality flag		CODE_QUALITY
prfStat	real	4	N(0,1)	Profile statistic		CLASS_STAR/GALAXY
prfMag	real	4	instrumental units	Profile magnitude		PHOT_PHG_MAG
gMag	real	4	mag	Magnitude calculated on assumption object is galaxy		MODEL_MAG_VALUE
sMag	real	4	mag	Magnitude calculated on assumption object is star		MODEL_MAG_VALUE
SSAfield	smallint	2		SSS field number (ESO/SRC system) that this detection falls in.		ID_FIELD
seam	smallint	2		Seam index: = zero or SSAfield for seamless selection		ID_FIELD
Total length		228