Gravity Seminar: Anna Lisa Varri

(University of Edinburgh)

Title: Rotating stellar systems and their black holes

Abstract: The study of self-gravitating spheroidal rotating bodies is a classical fluid dynamics problem with a distinguished history, yet its kinetic counterpart has rarely been explored. As an example, I will present a family of self-consistent kinetic equilibria describing uniformly rotating, axisymmetric quasi-isothermal stellar systems. Such equilibria define a singular perturbation Vlasov-Poisson problem with a free boundary which can be approached by means of an asymptotic expansion based on the rotation strength parameter. I will then illustrate an extension to the case of self-consistent equilibria with a central black hole. Explicit asymptotic results are obtained over three nested regimes surrounding the sharp transition between equilibria dominated by the mass of the host stellar system or by the mass of the central black hole. I will conclude by discussing the astrophysical implications of these results for current multi-messanger explorations of black hole demographics.