The starting point for the PS1 data archive is at Pan-STARRS1 data archive home page.


Description: Contains the photometry of individual detections from a difference image. The identifiers connecting the detection back to the difference image and to the object association are provided. PSF, aperture, and Kron (1980) photometry are included, along with sky and detector coordinate positions. Statistics References: Kron, R. G. 1980, ApJS, 43, 305.
NameUnitData TypeSizeDefault ValueDescription
diffObjIDdimensionlessBIGINT8NAUnique difference object identifier.
uniquePspsDFiddimensionlessBIGINT8NAUnique internal PSPS difference detection identifier.
diffDetIDdimensionlessBIGINT8NAUnique difference detection identifier.
diffImageIDdimensionlessBIGINT8NADifference detection meta identifier.
ippObjIDdimensionlessBIGINT8NAIPP internal object identifier.
ippDetectIDdimensionlessBIGINT8NAIPP internal detection identifier.
fromPosImagedimensionlessTINYINT1NADetection is from positive image (if 1) or negative image (if 0).
filterIDdimensionlessTINYINT1NAFilter identifier. Details in the Filter table.
surveyIDdimensionlessTINYINT1NASurvey identifier. Details in the Survey table.
randomDiffIDdimensionlessFLOAT8NARandom value drawn from the interval between zero and one.
tessIDdimensionlessTINYINT10Tessellation identifier. Details in the TessellationType table.
projectionIDdimensionlessSMALLINT2-1Projection cell identifier.
skyCellIDdimensionlessTINYINT1255Skycell region identifier.
dvoRegionIDdimensionlessINT4-1Internal DVO region identifier.
obsTimedaysFLOAT8-999Modified Julian Date at the midpoint of the observation. Note these are international atomic time rather than UTC, so if you want UTC times you will need to add 34 or 35 seconds to correct for leap seconds.
xPossky pixelsREAL4-999PSF x center location.
yPossky pixelsREAL4-999PSF y center location.
xPosErrsky pixelsREAL4-999Error in PSF x center location.
yPosErrsky pixelsREAL4-999Error in PSF y center location.
pltScalearcsec/pixelREAL4-999Local plate scale at this location.
posAngledegreesREAL4-999Position angle (sky-to-chip) at this location.
radegreesFLOAT8-999Right ascension.
decdegreesFLOAT8-999Declination.
raErrarcsecREAL4-999Right ascension error.
decErrarcsecREAL4-999Declination error.
zpmagnitudesREAL40Photometric zeropoint. Necessary for converting listed fluxes and magnitudes back to measured ADU counts.
telluricExtmagnitudesREAL4NAEstimated Telluric extinction due to non-photometric observing conditions. Necessary for converting listed fluxes and magnitudes back to measured ADU counts.
expTimesecondsREAL4-999Exposure time of the positive single-epoch image. Necessary for converting listed fluxes and magnitudes back to measured ADU counts.
airMassdimensionlessREAL40Airmass at midpoint of the exposure. Necessary for converting listed fluxes and magnitudes back to measured ADU counts.
DpsfFluxJanskysREAL4-999Flux from PSF fit.
DpsfFluxErrJanskysREAL4-999Error in PSF flux.
xPosChipraw pixelsREAL4-999PSF x position in original chip pixels.
yPosChipraw pixelsREAL4-999PSF y position in original chip pixels.
ccdIDdimensionslessSMALLINT2-999OTA identifier of original chip (see ImageMeta).
DpsfMajorFWHMarcsecREAL4-999PSF major axis FWHM.
DpsfMinorFWHMarcsecREAL4-999PSF minor axis FWHM.
DpsfThetadegreesREAL4-999PSF major axis orientation.
DpsfCoredimensionlessREAL4-999PSF core parameter k, where F = F0 / (1 + k r^2 + r^3.33).
DpsfQfdimensionlessREAL4-999PSF coverage factor.
DpsfQfPerfectdimensionlessREAL4-999PSF-weighted fraction of pixels totally unmasked.
DpsfChiSqdimensionlessREAL4-999Reduced chi squared value of the PSF model fit.
DpsfLikelihooddimensionlessREAL4-999Likelihood that this detection is best fit by a PSF.
DmomentXXarcsec^2REAL4-999Second moment M_xx.
DmomentXYarcsec^2REAL4-999Second moment M_xy.
DmomentYYarcsec^2REAL4-999Second moment M_yy.
DmomentR1arcsecREAL4-999First radial moment.
DmomentRHarcsec^0.5REAL4-999Half radial moment (r^0.5 weighting).
DapFluxJanskysREAL4-999Aperture flux.
DapFluxErrJanskysREAL4-999Error in aperture flux.
DapFillFdimensionlessREAL4-999Aperture fill factor.
DkronFluxJanskysREAL4-999Kron (1980) flux.
DkronFluxErrJanskysREAL4-999Error in Kron (1980) flux.
DkronRadarcsecREAL4-999Kron (1980) radius.
diffNPossky pixelsINT4-999Number of difference pixels within the aperture that are positive.
diffFPosRatiodimensionlessREAL4-999Ratio of the sum of positive flux pixel values to the sum of the absolute value of all unmasked pixel within the aperture.
diffNPosRatiodimensionlessREAL4-999Ratio of the number of positive flux pixels to the number of unmasked pixels within the aperture.
diffNPosMaskdimensionlessREAL4-999Ratio of the number of positive flux pixels to the number of positive or masked pixels within the aperture.
diffNPosAlldimensionlessREAL4-999Ratio of the number of positive flux pixels to the total number of all pixels within the aperture.
diffPosDistsky pixelsREAL4-999Distance to matching source in positive image.
diffNegDistsky pixelsREAL4-999Distance to matching source in negative image.
diffPosSNdimensionlessREAL4-999Signal to noise of matching source in positive image.
diffNegSNdimensionlessREAL4-999Signal to noise of matching source in negative image.
DskyJanskys/arcsec^2REAL4-999Background sky level.
DskyErrJanskys/arcsec^2REAL4-999Error in background sky level.
DinfoFlagdimensionlessBIGINT80Information flag bitmask indicating details of the photometry. Values listed in DetectionFlags.
DinfoFlag2dimensionlessINT40Information flag bitmask indicating details of the photometry. Values listed in DetectionFlags2.
DinfoFlag3dimensionlessINT40Information flag bitmask indicating details of the photometry. Values listed in DetectionFlags3.
processingVersiondimensionlessTINYINT1NAData release version.

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