A Dynamical Origin for Brown Dwarfs

Abstract

Brown dwarfs may have such low masses because they are prematurely ejected from small unstable multiple systems, while the members are still actively building up their masses. We demonstrate that this scenario is consistent with all currently existing observations of brown dwarfs, and propose further observational tests. We review the status of the latest realistic numerical simulations of disintegrating small N clusters, which show that many of the ejected members end up with masses that are substellar, drifting away from their birth region with velocities rarely exceeding 2 km/s.

10 pages, including 2 figures. To be published in the proceedings of the Cool Stars, Stellar Systems, and the Sun 12th Cambridge Workshop ``The Future of Cool-Star Astrophysics''