J/AJ/114/1488ivo://CDS.VizieR/J/AJ/114/1488doi:10.26093/cds/vizier.51141488CDSHolland S.Fahlman G.G.Richer H.B.2023-04-06T16:50:26Z1998-03-15T15:25:24ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frglobular-star-clustersphotometryWe present deep (V=~27) V- and I-band stellar photometry of G302 and G312, two globular star clusters in the halo of M31. These data were obtained using the Hubble Space Telescope's Wide Field/Planetary Camera 2. We find iron abundances of [Fe/H]=-1.85+/-0.12 for G302 and [Fe/H]=-0.56+/-0.03 for G312, consistent with spectroscopic measurements. The color-magnitude diagrams for each cluster show no evidence for an intermediate-aged population of stars, or a second parameter effect in the morphology of the horizontal branch. G302 shows no evidence for a color gradient but the inner regions of G312 are bluer than the outer regions. G312 shows no evidence of ellipticity or an extended halo of stars. G302 has a projected ellipticity of {epsilon}=0.195+/-0.012 with the projected major axis oriented towards the center of M31. G302 also shows evidence of an extended asymmetric stellar halo extending to at least twice the fitted Michie-King tidal radius. The amount of mass beyond the tidal radius of G302 is consistent with the stellar escape rates which have been predicted by N-body simulations of globular clusters in the Galactic tidal field. (c) 1997 American Astronomical Society.1997AJ....114.1488Hhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/114/1488CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/114/1488https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/114/1488http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/114/1488https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/114/1488https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/114/1488http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/114/1488GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapHSTOpticaldefaultJ/AJ/114/1488/table3Stellar photometry for G302 and the surrounding fieldsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCCDCCD the star was observed onmeta.id;instrcharIDIdentification number (1)meta.id;meta.mainintXposX pixel coordinate (2)pixpos.cartesian.x;instr.detfloatYposY pixel coordinate (2)pixpos.cartesian.y;instr.detfloatVmagV-band magnitudemagphot.mag;em.opt.Vfloate_Vmag1-sigma uncertainty in Vmagmagstat.errorfloat2_VmagValue of the DAOPHOT Chi statistics for Vmagstat.fit.chi2floatImagI-band magnitudemagphot.mag;em.opt.Ifloate_Imag1-sigma uncertainty in Imagmagstat.errorfloat2_ImagValue of the DAOPHOT Chi statistics for Imagstat.fit.chi2floatJ/AJ/114/1488/table4Stellar photometry for G312 and the surrounding fieldsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCCDCCD the star was observed onmeta.id;instrcharIDIdentification number (1)meta.id;meta.mainintXposX pixel coordinate (2)pixpos.cartesian.x;instr.detfloatYposY pixel coordinate (2)pixpos.cartesian.y;instr.detfloatVmagV-band magnitudemagphot.mag;em.opt.Vfloate_Vmag1-sigma uncertainty in Vmagmagstat.errorfloat2_VmagValue of the DAOPHOT Chi statistics for Vmagstat.fit.chi2floatImagI-band magnitudemagphot.mag;em.opt.Ifloate_Imag1-sigma uncertainty in Imagmagstat.errorfloat2_ImagValue of the DAOPHOT Chi statistics for Imagstat.fit.chi2floatJ/AJ/114/1488/table5Stellar photometry for G302XposX pixel coordinate (1)pixpos.cartesian.x;instr.detfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCCDCCD the star was observed onmeta.id;instrcharIDIdentification numbermeta.id;meta.mainintYposY pixel coordinate (1)pixpos.cartesian.y;instr.detfloatDistDistance of star from cluster centerarcsecpos.angDistancefloatVmagV-band magnitudemagphot.mag;em.opt.Vfloate_Vmag1-sigma uncertainty in Vmagmagstat.errorfloat2_VmagValue of the DAOPHOT Chi statistics for Vmagstat.fit.chi2floatImagI-band magnitudemagphot.mag;em.opt.Ifloate_Imag1-sigma uncertainty in Imagmagstat.errorfloat2_ImagValue of the DAOPHOT Chi statistics for Imagstat.fit.chi2floatJ/AJ/114/1488/table6Stellar Photometry for G312IDIdentification numbermeta.id;meta.mainintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCCDCCD the star was observed onmeta.id;instrcharXposX pixel coordinate (1)pixpos.cartesian.x;instr.detfloatYposY pixel coordinate (1)pixpos.cartesian.y;instr.detfloatDistDistance of star from cluster centerarcsecpos.angDistancefloatVmagV-band magnitudemagphot.mag;em.opt.Vfloate_Vmag1-sigma uncertainty in Vmagmagstat.errorfloat2_VmagValue of the DAOPHOT Chi statistics for Vmagstat.fit.chi2floatImagI-band magnitudemagphot.mag;em.opt.Ifloate_Imag1-sigma uncertainty in Imagmagstat.errorfloat2_ImagValue of the DAOPHOT Chi statistics for Imagstat.fit.chi2float