Name    E_mail_Address  Scientific_Session      Contribution_type       Title   Authors_affiliations    Abstract
Davies                    Oluwasegun           Ishola   segun_davies@yahoo.com  EAS Symp.6:Dynamics of Galaxies and Galactic Nuclei.    poster  Evidences for the presence of an intermediate mass black holes in Omega Centauri.       Ianramsey Institute     The globular cluster Omega Centauri is one of the largest and most massive members of the galactic system. However, its classification as a globular cluster has been challenged making it a candidate for being the stripped core of an accreted dwarf galaxy; this together with the fact that it has one of the largest velocity dispersions for star clusters in our galaxy makes it an interesting candidate for harboring an intermediate mass black hole. I we measure the surface brightness profile from integrated light on an HST/ACS image of the center, and find a central power-law cusp of logarithmic slope -0.08. We analyze Gemini GMOS-IFU kinematic data for a 5x5 arcsec field centered on the nucleus of the cluster, as well as for a field 14 arcsec
 away.

I detect a clear rise in the velocity dispersion from 18.6 km/s at 14 arcsec to 23 km/s in the center. Given the very large nearly flat core in Omega Cen (2.58 marcmin), an increase in the dispersion in the central 10 arcsec is difficult to attribute to stellar remnants. An isotropic, spherical dynamical model requires a highly concentrated configuration of dark remnants assuming a constant M/L of 2.7 for the visible stars within the core. We create a series of orbit-based models in order to explore possible anisotropies that would produce the observed velocity dispersion rise. The best-fit model rules out such anisotropies and implies a black hole mass of 4.0+/-1.0x10^4 M_sun, and excludes the no black hole case at a great significance