J/ApJ/347/251ivo://CDS.VizieR/J/ApJ/347/251doi:10.26093/cds/vizier.13470251CDSPeterson Ruth C.Seitzer PatrickCudworth Kyle M.2013-03-05T06:33:31Z1997-12-09T20:46:04ZCDS support team

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

cds-question@unistra.frglobular-star-clustersradial-velocityThe velocity dispersion as a function of radius in the globular cluster M15 is derived from measurements of 120 individual stars between 0.1' and 4.6' of the cluster center, and from the integrated light of the central cusp. The stellar measurements, with an individual accuracy of 1 km/s, indicate a mean cluster velocity of -107.1+/-0.9 km/s, and a mean velocity dispersion of 9.0+/-0.6 km/s. The velocity dispersion inside 1' varies with radius. The dispersion of the 27 stars within 20" is 14.2+/-1.9 km/s, while that of the 30 stars between 0.5' and 1.2' is 8.4+/-1.4 km/s. The cusp itself appears to have a dispersion of at least 25 km/s. Except for its greater velocity broadening, the spectrum of the integrated light of the cusp is indistinguishable from that formed by superposition of the individual M15 giant spectra, demonstrating that the excess light at the center is due primarily to the normal M15 population. The increase of the dispersion toward the center is not consistent with truncated isothermal (King-Michie) models, for which the velocity dispersion is nearly constant within a few core radii and then falls steeply beyond. The observed behaviour is difficult to reconcile as well with current post-core collapse models, which are also isothermal and whose central energy sources are modest. It is indicative of a nonthermal energy distribution with substantial heating in the central regions; this is consistent with a central black hole of about 1000 M_{sun}_.1989ApJ...347..251Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/347/251CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AJ/106/154 : HST Observations in inner region of M15 (Ferraro+ 1993)J/AJ/107/1745 : HST UVI photometry of M5. II. (Yanny+, 1994)J/AJ/107/2067 : Fabry-Perot measurements of M15 (Gebhardt+, 1994)J/AJ/110/704 : RR Lyrae in M15 (Silbermann+ 1995)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/347/251https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/347/251http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/347/251https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/347/251https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/347/251http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/347/251GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/347/251/table1 (Velocities for M15 members)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/347/251/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/347/251/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/347/251/table1?GETtext/xml+votable180.050000true322.493536312.1666750.005555555555555556Cone search capability for table J/ApJ/347/251/table3 (Velocities for M15 nonmembers)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/347/251/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/347/251/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/347/251/table3?GETtext/xml+votable180.050000true322.480883512.18563740.0055555555555555566/12405https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/347/251?format=asciiOpticaldefaultJ/ApJ/347/251/table1Velocities for M15 membersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJD-2440000Julian date (-2440000) of each observationdtime.epochfloatRA1950Right ascension (equinox 1950.0)pos.eq.ra;meta.mainDE1950Declination (equinox 1950.0)pos.eq.dec;meta.mainDistRadial distance from cluster centerarcminphys.angSizefloatPAPosition angle positive north through eastdegpos.posAngfloatRVMeasured radial velocitykm/sphys.veloc;pos.heliocentricdoublee_RVInternal uncertainty in RVkm/sstat.errorfloatVmag[]? V magnitudemagphot.mag;em.opt.VfloatnullableKustner[]? Number from Kustner (1921VeUSB..15....1K)meta.idintnullableOtherOther star namemeta.id;meta.mainchar_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data)pos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data)pos.eq.decnullableindexedJ/ApJ/347/251/table2Stars with multiple velocity measurementsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJD-2440000Julian date (-2440000)dtime.epochfloatRVMeasured radial velocitykm/sphys.veloc;pos.heliocentricdoublee_RVInternal uncertainty in RVkm/sstat.errorfloatKustner[]? Number from Kustner (1921VeUSB..15....1K)meta.idintnullableOtherOther star namemeta.idcharJ/ApJ/347/251/table3Velocities for M15 nonmembersVmagV magnitudemagphot.mag;em.opt.VfloatKustnerNumber from Kustner (1921VeUSB..15....1K)meta.id;meta.mainintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJD-2440000Julian date (-2440000) of each observationdtime.epochfloatRA1950Right ascension (equinox 1950.0)pos.eq.ra;meta.mainDE1950Declination (equinox 1950.0)pos.eq.dec;meta.mainRVMeasured radial velocitykm/sphys.veloc;pos.heliocentricdoublee_RVInternal uncertainty in RVkm/sstat.errorfloat_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data)pos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data)pos.eq.decnullableindexed