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arXiv · cond-mat/0208230

The Antonov problem for rotating systems

Abstract

We study the classical Antonov problem (of retrieving the statistical equilibrium properties of a self-gravitating gas of classical particles obeying Boltzmann statistics in space and confined in a spherical box) for a rotating system. It is shown that a critical angular momentum $λ_c$ (or, in the canonical language, a critical angular velocity $ω_c$) exists, such that for $λ<λ_c$ the system's behaviour is qualitatively similar to that of a non-rotating gas, with a high energy disordered phase and a low energy collapsed phase ending with Antonov's limit, below which there is no equilibrium state. For $λ>λ_c$, instead, the low-energy phase is characterized by the formation of two dense clusters (a ``binary star''). Remarkably, no Antonov limit is found for $λ>λ_c$. The thermodynamics of the system (phase diagram, caloric curves, local stability) is analyzed and compared with the recently-obtained picture emerging from a different type of statistics which forbids particle overlapping.

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BibTeXRIS

A. De Martino, E. V. Votyakov, D. H. E. Gross. 2003-01-23. The Antonov problem for rotating systems. https://doi.org/10.1016/s0550-3213(03)00050-6

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