Eur. Phys. J. B 29, 593-603 (2002)
https://doi.org/10.1140/epjb/e2002-00317-4

Thermodynamics of rotating self-gravitating systems

Hahn-Meitner-Institut, Bereich Theoretische Physik, Glienickerstr. 100, 14109 Berlin, Germany

Corresponding author: ^a demartino@hmi.de

Received: 8 July 2002
Published online: 15 October 2002

Abstract

We investigate the statistical equilibrium properties of a system of classical particles interacting via Newtonian gravity, enclosed in a three-dimensional spherical volume. Within a mean-field approximation, we derive an equation for the density profiles maximizing the microcanonical entropy and solve it numerically. At low angular momenta, i.e. for a slowly rotating system, the well-known gravitational collapse “transition” is recovered. At higher angular momenta, instead, rotational symmetry can spontaneously break down giving rise to more complex equilibrium configurations, such as double-clusters (“double stars”). We analyze the thermodynamics of the system and the stability of the different equilibrium configurations against rotational symmetry breaking, and provide the global phase diagram.