
diffObjID       dimensionless   BIGINT  8       NA      diff object identifier
uniquePspsDFid  dimensionless   BIGINT  8       NA      unique psps id (combination of batch_id, and counter) provided by ipptopsps
diffDetID       dimensionless   BIGINT  8       NA      diff detection identifier
diffDetMetaID   dimensionless   BIGINT  8       NA      diff detection meta identifier
ippDetectID     dimensionless   BIGINT  8       NA      ipp detection id generated by IPP
ippObjID        dimensionless   BIGINT  8       NA      ipp object id generated by IPP
filterID        dimensionless   TINYINT 1       NA      filter ID: g=1, r=2, i=3, z=4, y=5, w=6, ...
surveyID        dimensionless   TINYINT 1       NA      survey flag identifierr
randomDiffID    dimensionless   FLOAT   8       NA      random diff id  
skyCellID       dimensionless   REAL    4       -999    single float giving PrimaryCell.SkyCell identifier 
dvoRegionID     dimensionless   INT     4          0    identifier to dvo spatial region
obsTime         MeanJulianDays  FLOAT   8       -999    Time of mid observation of positive detection in Mean Julian Days of positive detection
xPos            pixels          REAL    4       -999    measured x on diff image sky cell PSF fit
yPos            pixels          REAL    4       -999    measured y on diff image sky cell from PSF fit
xPosErr         pixels          REAL    4       -999    estimated error in x
yPosErr         pixels          REAL    4       -999    estimated error in y
pltScale        arcsec/pix      REAL    4       -999    plate scale at this location (from DVO)
posAngle        degrees         REAL    4       -999    position angle (sky-to-chip) at this location (from DVO)
----------------------------------------------------    next 8 came from old DiffDetCalib, zp derived from cpt tables of BOTH images 
ra              degrees         FLOAT   8       NA      Right Ascension
dec             degrees         FLOAT   8       NA      Declination
raErr           arcsec          REAL    4       NA      Right Ascension error -> posErr because RA,Dec same?
decErr          arcsec          REAL    4       NA      Declination error
zp              magnitude       REAL    4       0       zeropoint (all that is needed to convert adu/sec to AB mag), no zpErr
telluricExt     magnitude       REAL    4       NA      estimated extinction due to non-photometric conditions  
expTime         seconds         REAL    4       -999    exposure time (informational)
airMass         dimensionless   REAL    4       0       airmass (informational)
-----------------------------------------------------   attributes of positive detection
DpsfFlux        Jy              REAL    4       -999    PSF flux
DpsfFluxErr     Jy              REAL    4       -999    PSF flux error
DpsfMajorFWHM   arcsec          REAL    4       -999    model PSF width in major axis
DpsfMinorFWHM   arcsec          REAL    4       -999    model PSF width in minor axis
DpsfTheta       degrees         REAL    4       -999    model PSF orientation angle degrees East of North
DpsfCore        dimensionless   REAL    4       -999    model PSF core parameter [k in (1 + kz + z^1.66)]
DpsfQf          dimensionless   REAL    4       -999    PSF coverage factor
DpsfQfPerfect   dimensionless   REAL    4       -999    PSF-weighted fraction of pixels totally unmasked
DpsfChiSq       dimensionless   REAL    4       -999    reduced-chisq of the psf model fit. (ndof?, npix?)
DpsfLikelihood  dimensionless   REAL    4       -999    PSF likelihood
DmomentXX       arcsec^2        REAL    4       -999    moment XX
DmomentXY       arcsec^2        REAL    4       -999    moment XY
DmomentYY       arcsec^2        REAL    4       -999    momeny YY
DmomentR1       arcsec          REAL    4       -999    first radial moment 
DmomentRH       arcsec          REAL    4       -999    r^1/2 weighted moment
DmomentM3C      arcsec^3        REAL    4       -999    3rd moment sin(theta) 
DmomentM3S      arcsec^3        REAL    4       -999    3rd moment cos(theta) 
DmomentM4C      arcsec^4        REAL    4       -999    4th moment sin(theta)
DmomentM4S      arcsec^4        REAL    4       -999    4th moment cos(theta) 
DapFlux         Jy              REAL    4       -999    Aperture flux
DapFluxErr      Jy              REAL    4       -999    Aperture flux error
DapFillF        dimensionless   REAL    4       -999    Aperture fill factor 
DkronFlux       Jy              REAL    4       -999    Kron flux
DkronFluxErr    Jy              REAL    4       -999    Kron flux error
DkronRad        arcsec          REAL    4       -999    Kron radius
------------------------------------------------------- from diff image cmf/smf files 
diffNPos        dimensionless   REAL    4       -999    npix > 3sigma
diffFRatio      dimensionless   REAL    4       -999    fPos/(fPos +fNeg)
diffNBad        dimensionless   REAL    4       -999    nPos/(nPos+nNeg)
diffNMask       dimensionless   REAL    4       -999    nPos/(nPos + nMask)
diffNAll        dimensionless   REAL    4       -999    nPos/(nPos + nMask + nNeg)
diffPdist       arcsec          REAL    4       -999    distance to positive match source
diffNdist       arcsec          REAL    4       -999    distance to negative match source
diffPSN         dimensionless   REAL    4       -999    signal to noise of pos match source
diffNSN         dimensionless   REAL    4       -999    signal to noise of neg match source
-------------------------------------------------------
Dsky            adu/sec/pixel   REAL    4       -999    PSF sky level at source
DskyErr         adu/sec/pixel   REAL    4       -999    estimated error in sky
DinfoFlag       dimensionless   INT     4       -999    flag indicating provenance information
DinfoFlag2      dimensionless   INT     4       -999    flag indicating provenance information
DinfoFlag3      dimensionless   INT     4       -999    flag indicating provenance information
dataRelease     dimensionless   TINYINT 1       NA      Data release when this detection was originally taken. Recalibrations do not affect this value.
