A Fokker-Planck model of Dense Rotating Stellar Clusters

Previous abstract Next abstract

Session 24 -- AGNs/QSOs - High Luminosity
Display presentation, Tuesday, June 13, 1995, 9:20am - 6:30pm

[24.12] A Fokker-Planck model of Dense Rotating Stellar Clusters

John Girash (CfA)

We present first results from a numerical model of dense stellar clusters ($\rho\sim10^7~M_\odot{\rm~pc}^{-3}$) at the centres of galaxies, using the orbit-averaged Fokker-Planck equation in two-dimensional action-angle space. The model expands the work of Quinlan \& Shapiro (1990 ApJ \bf356\rm, 483, ``Q\&S'') to include rotation and associated effects, ellipticity and angular momentum. A non-axisymmetric component of the potential (i.e. the formation of a stellar bar) is invoked to increase the efficiency of angular momentum transport. Following Q\&S we include $\sim10$ distribution functions, each representing a stellar population a factor of two more massive than the next; in addition there will be a separate, non-collisional bar-star distribution function: the other stars interact with the bulk potential of these bar stars. Future enhancements will include the effects of stellar evolution and collisions.

The goal is to verify that angular momentum can be removed from the core of the cluster quickly enough so that the constraint of rotational support no longer prevents the formation of a massive ($\sim1000M_\odot$) object at the centre. This could act as the seed black hole for the formation of an active galactic nucleus.

Tuesday program listing