J/ApJ/986/80ivo://CDS.VizieR/J/ApJ/986/80doi:10.26093/cds/vizier/ba-yt-2gCDSGriggio M.Bellini A.Aros F.I.Vesperini E.Libralato M.Anderson J.,Baumgardt H.Ferraro F.R.van der Marel R.P.Raso S.Renzini A.,Rest A.Ryan R.E.Jr2026-07-02T12:01:20Z2025-12-01T14:34:50ZCDS support team

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

cds-question@unistra.frglobular-star-clustersphotometryproper-motionsWe use new HST observations coupled with archival data spanning a total temporal baseline of 17 years to study the internal kinematics of the multiple populations in the globular cluster NGC 2808 from its center out to ~8 half-light radii (r_h_). We detect different kinematical behaviors between the first- and second-generation populations. This is especially evident towards the external regions of the cluster, where second-generation stars are increasingly more radially anisotropic. Our results are in agreement with theoretical simulations that predict that second-generation stars, initially more concentrated in the inner regions, gradually diffuse outward and develop a stronger radially anisotropic velocity distribution with respect to the first-generation stars. We find the central regions of the cluster to exhibit a higher degree of energy equipartition than the outskirts; our analysis reveals similar levels of energy equipartition in the radial and tangential components of the motion within about 4r_h_ , while outside 4r_h_ the data suggest that the equipartition level of the radial component of the velocity dispersion is slightly higher than that of the tangential component. Finally, we measured the dispersion of the angular momentum Lz for the three main subpopulations along the main sequence, which provides further evidence of the differences in the velocity anisotropy of 1G and 2G stars and shows marginal evidence for the most extreme second-generation subpopulation being slightly more radially anisotropic than the other second-generation subpopulation.2025ApJ...986...80Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/986/80CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/986/80https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/986/80http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/986/80https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/986/80https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/986/80http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/986/80GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/986/80/ngc2808 (Astrometric catalog)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/986/80/ngc2808?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/986/80/ngc2808?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/986/80/ngc2808?GETtext/xml+votable180.050000true137.9695584235013-64.92966451264610.0055555555555555566/372942.0401237512456292e-19 2.706461185444514e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/986/80?format=asciidefaultJ/ApJ/986/80/ngc2808Astrometric catalog_RA.icrsRight ascension (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.raindexed_DE.icrsDeclination (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.decindexedrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRA_ICRSRight ascension (ICRS) at Ep=2016.0degpos.eq.ra;meta.mainindexedDE_ICRSDeclination (ICRS) at Ep=2016.0degpos.eq.dec;meta.mainindexedpmRAProper motion along right ascension (1)mas/yrpos.pm;pos.eq.radoublee_pmRAError on pmRAmas/yrstat.error;pos.pm;pos.eq.radoublepmDEProper motion along declination (1)mas/yrpos.pm;pos.eq.decdoublee_pmDEError on pmDEmas/yrstat.error;pos.pm;pos.eq.decdoublecxchi2 of the pmRA fitstat.fit.chi2floatcychi2 of the pmDE fitstat.fit.chi2floatlsNumber of epochs where the source was measuredmeta.numberintuNumber of epochs used in the fitmeta.numberintdtTemporal baseline of the data used in the fityrtime.intervalfloatgoodFlag equal to one if the source passed our cuts, zero otherwisemeta.codeintpopID[0/3] Population tagging (1 = bMS, 2 = mMS, 3 = rMS)src.sampleintgoodHRC[0/1] Flag equal to one if the source passed our cuts, zero otherwise (only applies to stars measured in HRC data)meta.codeintnStarStar numbermeta.id;meta.mainintJ/ApJ/986/80/f275w4ph*Photometric catalog for filter F275W and epoch 4recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmF275W? Magnitude in F275W band (Vega)magphot.mag;em.UV.200-300nmfloatnullablee_mF275W? Error on magnitudemagstat.errorfloatnullableqfitQuality of fitmeta.code.qualfloatradxsRadxs parametermeta.codefloatoFraction of flux contamination due to neighborsstat.fit.paramdoublefNumber of images where the source was foundmeta.numberintgNumber of images used to measure the sourcemeta.numberintnStarStar numbermeta.id;meta.mainintJ/ApJ/986/80/f275w5ph*Photometric catalog for filter F275W and epoch 5recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmF275W? Magnitude in F275W band (Vega)magphot.mag;em.UV.200-300nmfloatnullablee_mF275W? Error on magnitudemagstat.errorfloatnullableqfitQuality of fitmeta.code.qualfloatradxsRadxs parametermeta.codefloatoFraction of flux contamination due to neighborsstat.fit.paramdoublefNumber of images where the source was foundmeta.numberintgNumber of images used to measure the sourcemeta.numberintnStarStar numbermeta.id;meta.mainintJ/ApJ/986/80/f475w1ph*Photometric catalog for filter F475W and epoch 1recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmF475W? Magnitude in F475W band (Vega)magphot.mag;em.opt.Bfloatnullablee_mF475W? Error on magnitudemagstat.errorfloatnullableqfitQuality of fitmeta.code.qualfloatradxsRadxs parametermeta.codefloatoFraction of flux contamination due to neighborsstat.fit.paramdoublefNumber of images where the source was foundmeta.numberintgNumber of images used to measure the sourcemeta.numberintnStarStar numbermeta.id;meta.mainintJ/ApJ/986/80/f475w2ph*Photometric catalog for filter F475W and epoch 2recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmF475W? Magnitude in F475W band (Vega)magphot.mag;em.opt.Bfloatnullablee_mF475W? Error on magnitudemagstat.errorfloatnullableqfitQuality of fitmeta.code.qualfloatradxsRadxs parametermeta.codefloatoFraction of flux contamination due to neighborsstat.fit.paramdoublefNumber of images where the source was foundmeta.numberintgNumber of images used to measure the sourcemeta.numberintnStarStar numbermeta.id;meta.mainintJ/ApJ/986/80/f475w4ph*Photometric catalog for filter F475W and epoch 4recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmF475W? Magnitude in F475W band (Vega)magphot.mag;em.opt.Bfloatnullablee_mF475W? Error on magnitudemagstat.errorfloatnullableqfitQuality of fitmeta.code.qualfloatradxsRadxs parametermeta.codefloatoFraction of flux contamination due to neighborsstat.fit.paramdoublefNumber of images where the source was foundmeta.numberintgNumber of images used to measure the sourcemeta.numberintnStarStar numbermeta.id;meta.mainintJ/ApJ/986/80/f475w5ph*Photometric catalog for filter F475W and epoch 5recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmF475W? Magnitude in F475W band (Vega)magphot.mag;em.opt.Bfloatnullablee_mF475W? Error on magnitudemagstat.errorfloatnullableqfitQuality of fitmeta.code.qualfloatradxsRadxs parametermeta.codefloatoFraction of flux contamination due to neighborsstat.fit.paramdoublefNumber of images where the source was foundmeta.numberintgNumber of images used to measure the sourcemeta.numberintnStarStar numbermeta.id;meta.mainintJ/ApJ/986/80/f814w2ph*Photometric catalog for filter F814W and epoch 2recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmF814W? Magnitude in F814W band (Vega)magphot.mag;em.opt.Ifloatnullablee_mF814W? Error on magnitudemagstat.errorfloatnullableqfitQuality of fitmeta.code.qualfloatradxsRadxs parametermeta.codefloatoFraction of flux contamination due to neighborsstat.fit.paramdoublefNumber of images where the source was foundmeta.numberintgNumber of images used to measure the sourcemeta.numberintnStarStar numbermeta.id;meta.mainintJ/ApJ/986/80/f814w4ph*Photometric catalog for filter F814W and epoch 4recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmF814W? Magnitude in F814W band (Vega)magphot.mag;em.opt.Ifloatnullablee_mF814W? Error on magnitudemagstat.errorfloatnullableqfitQuality of fitmeta.code.qualfloatradxsRadxs parametermeta.codefloatoFraction of flux contamination due to neighborsstat.fit.paramdoublefNumber of images where the source was foundmeta.numberintgNumber of images used to measure the sourcemeta.numberintnStarStar numbermeta.id;meta.mainintJ/ApJ/986/80/f814w5ph*Photometric catalog for filter F814W and epoch 5recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmF814W? Magnitude in F814W band (Vega)magphot.mag;em.opt.Ifloatnullablee_mF814W? Error on magnitudemagstat.errorfloatnullableqfitQuality of fitmeta.code.qualfloatradxsRadxs parametermeta.codefloatoFraction of flux contamination due to neighborsstat.fit.paramdoublefNumber of images where the source was foundmeta.numberintgNumber of images used to measure the sourcemeta.numberintnStarStar numbermeta.id;meta.mainintJ/ApJ/986/80/f275-814Photometric catalogs in the F275W and F814W filters as used in the paper, corrected for differential reddeningrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmF275W? Magnitude in F275W band (Vega) (1)magphot.mag;em.UV.200-300nmfloatnullablemF814W? Magnitude in F814W band (Vega) (1)magphot.mag;em.opt.IfloatnullableDRcDifferential reddening correction along the reddening vectorarith.factorfloate_DRcError on DRcstat.errorfloatnuNumber of stars used to compute DRcmeta.numberintruMaximun distance of the stars used to compute DRc [UVIS pixels]pixpos.cartesian;instr.detintuse[0/1] Flag equal to one if the star was measured in both filters, zero otherwisemeta.code.qualintnStarStar numbermeta.id;meta.mainintJ/ApJ/986/80/f475-814Photometric catalogs in the F475W and F814W filters as used in the paper, corrected for differential reddeningrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmF475W? Magnitude in F475W band (Vega) (1)magphot.mag;em.opt.BfloatnullablemF814W? Magnitude in F814W band (Vega) (1)magphot.mag;em.opt.IfloatnullableDRcDifferential reddening correction along the reddening vector (2)arith.factorfloate_DRcError on DRcstat.errorfloatnuNumber of stars used to compute DRcmeta.numberintruMaximum distance of the stars used to compute DRc [UVIS pixels]pixpos.cartesian;instr.detintuse[0/1] Flag equal to one if the star was measured in both filters, zero otherwisemeta.code.qualintnStarStar numbermeta.id;meta.mainint