Abstract Details
| Name: Dipanweeta Bhattacharyya Affiliation: Indian Institute of Astrophysics, Bangalore Conference ID: ASI2016_552 Title : $M-\sigma$ relationship and Galactic structure Authors and Co-Authors : A. Mangalam (Indian Institute of Astrophysics, Bangalore) Abstract Type : Poster Abstract Category : Extragalactic astronomy Abstract : There is a well known observed correlation between the mass, $M_\bullet$, of Supermassive black hole (SMBH) at the center of massive galaxies and velocity dispersion $\sigma$ of the stars in the galaxy with $M_{\bullet} \propto \sigma^p$ where $p=4-5$ is empirically indicated. We build stellar distribution functions (DF) for stellar systems around the black hole taking a form $f(E, J)$ of the Evans type that is constrained by typical intensity profiles of elliptical galaxies. We self-consistently calculate the $\sigma$ profile from the inverted stellar mass density derivable from the Nuker form, thereby deducing the total potential including the black hole. We thus derive the $M_\bullet-\sigma$ relation taking a constant ratio of bulge to black hole mass with dispersion calculated from various methods: sphere of influence, circular orbit velocities and also using the velocity dispersion profile directly constructed from the DF; we find constraints on the DF form so that the derived $p$ is in the range $4-5$ across the methods. The model can be applied to and parameters derived for few realistic systems for which the surface density profile, dynamical mass and observed velocity dispersion are available. |