Intermediate-Mass Black Holes in Galactic Nuclei and Starbursts

Northwestern University, Evanston IL

Investigators

Abstract

Abstract AST - 0607498 Rasio This project is about the black holes at the center of dense star clusters. The Principal Investigator and his team will carry out detailed supercomputer simulations of the processes that lead to the formation and collapse of such black holes. The two main classes of dynamical evolution paths that will be studied are: (i) the rapid contraction of young star clusters, leading to runaway collisions and mergers of ordinary stars and the production of a very massive remnant that could undergo direct gravitational collapse to a black hole; and (ii) the dynamical evolution of dense systems of stellar black holes, which can also merge together and grow rapidly in mass, as they form tight black hole binaries driven to complete coalescence by the energy loss to gravitational radiation. The computational methods will make it possible to study these problems for a wide range of systems, from small star clusters all the way to large proto-galactic nuclei, with a unified and realistic treatment of all-important astrophysical processes. The stellar dynamics computer codes developed for this project are general tools, which will be useful for studying many other problems involving dense star clusters with or without massive black holes. Some of the novel algorithms and numerical techniques are of wide applicability. The planned research activities will involve the training of several undergraduate students at Northwestern University, and will likely include students from under-represented minorities. Outreach activities are also planned, taking advantage of the resources of the nearby Adler Planetarium and Astronomy Museum in Chicago.