J/ApJ/595/187ivo://CDS.VizieR/J/ApJ/595/187doi:10.26093/cds/vizier.15950187CDSMcNamara B.J.Harrison T.E.Anderson J.2005-04-30T11:40:09Z2005-04-30T11:33:55ZCDS support team

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

cds-question@unistra.frglobular-star-clustersproper-motionsvisible-astronomybroad-band-photometryWe present the results of an internal proper motion analysis of the inner region of M15 using Hubble Space Telescope Wide Field Planetary Camera 2 images. The motions of 704 stars with brightnesses above that of the cluster turnoff (V<18.3) are analyzed to determine the velocity dispersion profile within about 15" of the cluster center. The average signal-to-noise ratio of these motions is about 3, and stars in the innermost radial bin have an average core distance of only 0.7". Assuming a distance to M15 of 10kpc, we estimate that the velocity dispersion within this innermost bin is 14.5+/-2.5km/s and that it slowly decreases outward, reaching a value of 9.8+/-0.8km/s at R=15.6". We find that the proper-motion dispersion profile is in good agreement with the predictions of recent N-body simulations that do not require the presence of a central intermediate-mass black hole (IMBH). The agreement between the observed profile and the N-body simulations is marginally improved if one assumes that when a neutron star is created as a result of stellar evolution, it escapes from the cluster. Based on the results of this study and a review of other investigations, it is concluded that there is little direct evidence that M15 possesses an intermediate-mass black hole.2003ApJ...595..187Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/595/187CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+AS/119/307 : Position in M15 (Le Campion+, 1996)J/AJ/106/154 : HST Observations in inner region of M15 (Ferraro+ 1993)J/AJ/107/1745 : HST UVI photometry of M15. II. (Yanny+, 1994)J/AJ/113/1026 : Fabry-Perot Observations of M15 (Gebhardt+ 1997)J/AJ/115/708 : Radial Velocities in the Field of M15 (Drukier+ 1998)J/AJ/119/1268 : CFHT adaptive optics observations of M15 (Gebhardt+, 2000)J/ApJ/602/264 : Proper motions and radial velocities in M15https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/595/187https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/595/187http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/595/187https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/595/187https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/595/187http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/595/187GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/ApJ/595/187/table2M15 Proper Motion DatarecnoRecord number assigned by the VizieR team. Should Not be used for identification.intXpixThe x position on HST image U2AS0201T (1)pixfloatYpixThe y position on HST image U2AS0201T (1)pixfloatXpmThe X pixel displacement relative proper motion over 8 years (in pix/8yr)0.125pix/yrfloatYpmThe Y pixel displacement relative proper motion over 8 years (in pix/8yr)0.125pix/yrfloate_XpmError in Xpm0.125pix/yrfloate_YpmError in Ypm0.125pix/yrfloatVmagUncalibrated instrumental V magnitudemagfloatB-VUncalibrated instrumental (B-V) magnitudemagfloatGIDGuhathakurta et al. (1996AJ....111..267G) identification numberintIM[0/1] Internal proper motion analysis (2)int