星系形态星表数据描述.doc

Zurich Structure & Morphology Catalog v1.0 DefinitionsCOSMOS OverviewThe COSMOS Archive serves data taken for the Cosmic Evolution Survey (COSMOS) project.COSMOS is an astronomical survey designed to probe the formation and evolution of galaxies as a function of cosmic time (redshift) and large scale structural environment. The survey covers a 2 square degree equatorial field with imaging by most of the major space-based telescopes (Hubble, Spitzer, GALEX, XMM, Chandra) and a number of large ground based telescopes (Subaru, VLA, ESO-VLT, UKIRT, NOAO, CFHT, and others).IRSA serves the COSMOS archive using the following search methods: Spatial search on all images and small catalogs, using Atlas Advanced search on only the larger catalogs, using GatorZurich Structure & Morphology Catalog v1.0 OverviewThis catalog contains the measurements presented in:1 1. Scarlata, Carollo, Lilly et al 2007, ApJS, 172, 406 (i.e., the Zurich Estimator of Structural Type ZEST catalog; measurements down to a limiting magnitude of I_AB=24. ZEST measurements for galaxies with half-light radii 22.5 - however, the quality of the fits deteriorates for sources substantially fainter than I_AB23)This v1.0 catalog is based on the May 2006 release % of Alexie Leauthauds ACS catalog (cut at the limits mentioned above)Notes:(a) All ACS_parameter columns are copied from the original May 2006 Leauthaud catalog(b) The catalog has been cross-correlated with the January 2006 Capak catalog.All Capak IDs, RAs, and Decs refer to this version of the ground-based photometric catalog, and provide the closest ground-based match to the ACS source within a radius of 0.6 arcseconds.(c) The catalog contains 71 colums and 131532 lines. Each line is written in fortran format: format(i9,1x,2d23.12,1x,a37,1x,67d23.12)(d) An entry of -999999 indicates no measurement (including in the ACS and Capak catalogs).(e) The pixel scale for the quantities in pixels is 0.03.Zurich Structure & Morphology Catalog v1.0 Column DefinitionsGator serves the Zurich Structure & Morphology Catalog v1.0 (76 columns 71 delivered + 5 IRSA-created, 131,532 data rows). The column descriptions can be found below.Column NameData TypeUnitsDescriptionSequentialIDintIdentification numberRAfloatdegreesRight ascensionDECfloatdegreesDeclinationCAPAK_IDfloatID based on ground-based photometric catalog of Capak 2006CAPAK_RAfloatdegreesClosest matched right ascension to ground-based catalog within 0.6CAPAK_DECfloatdegreesClosest matched declination to ground-based catalog within 0.6ACS_MAG_AUTOfloatTotal magnitude of object- used for catalog selectionACS_MAGERR_AUTOfloatmagnitudeMagnitude errorACS_X_IMAGEfloatpixelX-pixel position on ACS-tileACS_Y_IMAGEfloatpixelY-pixel position on ACS-tileACS_XPEAK_IMAGEfloatpixelX-pixel position of object peak flux on ACS tileACS_YPEAK_IMAGEfloatpixelY-pixel position of object peak flux on ACS tileACS_ALPHAPEAK_floatdegreesRA of object peak fluxACS_DELTAPEAK_floatdegreesDec of object peak fluxACS_A_IMAGEfloatSExtractor semi-major axisACS_B_IMAGEfloatSExtractor semi-minor axisACS_THETA_IMAGEfloatSExtractor position angleACS_ELONGATIONfloatSExtractor a/b semi-major axis / semi minor axisACS_CLASS_STARfloatSExtractor stellarity parameterACS_IDENTfloatUnique number that identifies objectACS_SEfloat1 = Detection from hot pass of SExtractor.0 = Detection from cold pass of SExtractor.ACS_MU_CLASSfloatType of object.1 = galaxy2 = star3 = spuriousACS_OVERLAPfloatObject overlap flag. All objects here have overlap =1 i.e. no overlap.ACS_NEARSTARfloatObject in star mask flag. All the objects in this morphological catalog have nearstar = 1 which means they are not in a star mask.ACS_MASKfloatObject in automatic mask flag.2 = star used to make automatic maskACS_MASKEDfloatObject in manual mask flag.-1 = manual mask (astrophysical obj)0 = manual mask (artifact or image defect)1 = not in manual maskACS_CLEANfloatObject useable flag.0 = do not use this object1 = use this objectACS_UNIQUEfloatObject unique flag. All the objects in this morphological catalog have unique = 1 which means they are all unique in the original ACS catalog.GGfloatZEST Gini coefficientM20floatZEST second order moment of the 20% brightest pixelsCCfloatZEST concentrationAAfloatZEST asymmetryR20floatpixelsZEST semi-major axis length of ellipse encompassing 20% of total lightR50floatpixelsZEST semi-major axis length of ellipse encompassing 50% of total lightR80floatpixelsZEST semi-major axis length of ellipse encompassing 80% of total lightRPETfloatpixelsZest semi-major axis length for Petrosian Radius ellipseFLAGRPETfloatPetrosian radius flag.0 = single Petrosian radius measured2 = multiple radii measured (noisy SB profile)5 = SB profile was corrected for diffuse light contribution from neighboring object(s)FLUX_GIM2DfloatcountsGIM2D total fluxLE_FLUX_GIM2DfloatLE_FLUX_GIM2D (99% conf. lower error on R_GIM2D)UE_FLUX_GIM2DfloatUE_FLUX_GIM2D (99% conf. lower error on R_GIM2D)R_GIM2DfloatarcsecondsGIM2D psf-convolved half-light radius of objectLE_R_GIM2Dfloat99% conf. lower error on R_GIM2DUE_R_GIM2Dfloat99% conf. upper error on R_GIM2DELL_GIM2DfloatGIM2D ellipticity = 1-b/a of objectLE_ELL_GIM2Dfloat99% conf. lower error on ELL_GIM2DUE_ELL_GIM2Dfloat99% conf. upper error on ELL_GIM2DPA_GIM2DfloatdegreesGIM2D position angle of object - cw from +y-axisLE_PA_GIM2Dfloat99% conf. lower error on PA_GIM2DUE_PA_GIM2Dfloat99% conf. upper error on PA_GIM2DDX_GIM2Dfloatarcsecondsx-offset of GIM2D-model center from ACS-coordinate centerLE_DX_GIM2Dfloat99% conf. lower error on DX_GIM2DUE_DX_GIM2Dfloat99% conf. upper error on DX_GIM2DDY_GIM2Dfloatarcsecondsy-offset of GIM2D-model center from ACS-coordinate centerLE_DY_GIM2Dfloat99% conf. lower error on DY_GIM2DUE_DY_GIM2Dfloat99% conf. upper error on DY_GIM2DSERSIC_N_GIM2DfloatGIM2D Sersic indexLE_N_GIM2Dfloat99% conf. lower error on SERSIC_N_GIM2DUE_N_GIM2Dfloat99% conf. upper error on SERSIC_N_GIM2DR_0P5_GIM2DfloatarcsecondsGIM2D half-light radius of object without PSF convolutionCHI_GIM2Dfloatreduced CHI2 of the best GIM2D model fitITER_GIM2Dfloatno. of iterations required for GIM2D fit to convergePC_1floatZEST first principal componentPC_2floatZEST second principal componentPC_3floatZEST third principal componentTYPEfloatZEST Type CLASS1 = Early type2 = Disk3 = Irregular Galaxy9 = no classificationBULGfloatZEST Bulgeness CLASS - only for Type 2 (disk) galaxies.0 = bulge dominated galaxy1,2 = intermediate-bulge galaxies3 =