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TABLE  PhotoObjDR7

Contains the spatial cross-match between DR8 photoobj and DR7 photoobj.
This is a unique match between a DR8 photoobj and a DR7 photoobj, and matches are restricted to the same run/camcol/field. The match radius is 1 arcsec, and within this radius preference is given to a photoprimary match over a secondary. If no primary match exists, the nearest secondary match is chosen. If more than one match of a given mode exists, the nearest one is chosen. The table contains the DR8 and DR7 objids and modes, the distance between them, and the DR7 phototag quantities.

nametypelengthunitucddescription
dr7objidbigint8 ID_MAINUnique DR7 identifier composed from [skyVersion,rerun,run,camcol,field,obj].
dr8objidbigint8 ID_MAINUnique DR8 identifier composed from [skyVersion,rerun,run,camcol,field,obj].
distancefloat8  Distance in arcmin between the DR7 and DR8 positions
modeDR7tinyint1 CLASS_OBJECTDR7 mode, 1: primary, 2: secondary, 3: family object.
modeDR8tinyint1 CLASS_OBJECTDR8 mode, 1: primary, 2: secondary, 3: family object.
skyVersiontinyint1 CODE_MISC0 = OPDB target, 1 = OPDB best
runsmallint2 OBS_RUNRun number
rerunsmallint2 CODE_MISCRerun number
camcoltinyint1 INST_IDCamera column
fieldsmallint2 ID_FIELDField number
objsmallint2 ID_NUMBERThe object id within a field. Usually changes between reruns of the same field.
nChildsmallint2 NUMBERNumber of children if this is a composite object that has been deblended. BRIGHT (in a flags sense) objects also have nchild == 1, the non-BRIGHT sibling.
typeLink to smallint2 CLASS_OBJECTMorphological type classification of the object.
probPSFreal4 STAT_PROBABILITYProbability that the object is a star. Currently 0 if type == 3 (galaxy), 1 if type == 6 (star).
insideMaskLink to tinyint1 CODE_MISCFlag to indicate whether object is inside a mask and why
flagsLink to bigint8 CODE_MISCPhoto Object Attribute Flags
psfMag_ureal4magPHOT_SDSS_UPSF flux
psfMag_greal4magPHOT_SDSS_GPSF flux
psfMag_rreal4magPHOT_SDSS_RPSF flux
psfMag_ireal4magPHOT_SDSS_IPSF flux
psfMag_zreal4magPHOT_SDSS_ZPSF flux
psfMagErr_ureal4magPHOT_SDSS_U ERRORPSF flux error
psfMagErr_greal4magPHOT_SDSS_G ERRORPSF flux error
psfMagErr_rreal4magPHOT_SDSS_R ERRORPSF flux error
psfMagErr_ireal4magPHOT_SDSS_I ERRORPSF flux error
psfMagErr_zreal4magPHOT_SDSS_Z ERRORPSF flux error
petroMag_ureal4magPHOT_SDSS_UPetrosian flux
petroMag_greal4magPHOT_SDSS_GPetrosian flux
petroMag_rreal4magPHOT_SDSS_RPetrosian flux
petroMag_ireal4magPHOT_SDSS_IPetrosian flux
petroMag_zreal4magPHOT_SDSS_ZPetrosian flux
petroMagErr_ureal4magPHOT_SDSS_U ERRORPetrosian flux error
petroMagErr_greal4magPHOT_SDSS_G ERRORPetrosian flux error
petroMagErr_rreal4magPHOT_SDSS_R ERRORPetrosian flux error
petroMagErr_ireal4magPHOT_SDSS_I ERRORPetrosian flux error
petroMagErr_zreal4magPHOT_SDSS_Z ERRORPetrosian flux error
petroR50_rreal4arcsecEXTENSION_RADRadius containing 50% of Petrosian flux
petroR90_rreal4arcsecEXTENSION_RADRadius containing 90% of Petrosian flux
modelMag_ureal4magPHOT_SDSS_U FIT_PARAMbetter of DeV/Exp magnitude fit
modelMag_greal4magPHOT_SDSS_G FIT_PARAMbetter of DeV/Exp magnitude fit
modelMag_rreal4magPHOT_SDSS_R FIT_PARAMbetter of DeV/Exp magnitude fit
modelMag_ireal4magPHOT_SDSS_I FIT_PARAMbetter of DeV/Exp magnitude fit
modelMag_zreal4magPHOT_SDSS_Z FIT_PARAMbetter of DeV/Exp magnitude fit
modelMagErr_ureal4magPHOT_SDSS_U ERRORbetter of DeV/Exp magnitude fit error
modelMagErr_greal4magPHOT_SDSS_G ERRORbetter of DeV/Exp magnitude fit error
modelMagErr_rreal4magPHOT_SDSS_R ERRORbetter of DeV/Exp magnitude fit error
modelMagErr_ireal4magPHOT_SDSS_I ERRORbetter of DeV/Exp magnitude fit error
modelMagErr_zreal4magPHOT_SDSS_Z ERRORbetter of DeV/Exp magnitude fit error
mRrCc_rreal4 FIT_PARAMAdaptive (<r^2> + <c^2>)
mRrCcErr_rreal4 FIT_PARAM ERRORError in adaptive (<r^2> + <c^2>)
lnLStar_rreal4 FIT_GOODNESSStar ln(likelihood)
lnLExp_rreal4 FIT_GOODNESSExponential disk fit ln(likelihood)
lnLDeV_rreal4 FIT_GOODNESSDeVaucouleurs fit ln(likelihood)
statusLink to int4 CODE_MISCStatus of the object in the survey
rafloat8degPOS_EQ_RA_MAINJ2000 right ascension (r')
decfloat8degPOS_EQ_DEC_MAINJ2000 declination (r')
cxfloat8 POS_EQ_CART_Xunit vector for ra+dec
cyfloat8 POS_EQ_CART_Yunit vector for ra+dec
czfloat8 POS_EQ_CART_Zunit vector for ra+dec
primTargetLink to int4 CODE_MISCBit mask of primary target categories the object was selected in.
secTargetLink to int4 CODE_MISCBit mask of secondary target categories the object was selected in.
extinction_ureal4magPHOT_EXTINCTION_GALExtinction in each filter
extinction_greal4magPHOT_EXTINCTION_GALExtinction in each filter
extinction_rreal4magPHOT_EXTINCTION_GALExtinction in each filter
extinction_ireal4magPHOT_EXTINCTION_GALExtinction in each filter
extinction_zreal4magPHOT_EXTINCTION_GALExtinction in each filter
htmIDbigint8 CODE_HTM20-deep hierarchical trangular mesh ID of this object
fieldIDbigint8 ID_FIELDLink to the field this object is in
SpecObjIDbigint8 ID_CATALOGPointer to the spectrum of object, if exists, else 0
sizereal4  computed: =SQRT(mRrCc_r/2.0)