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arXiv · 2209.05327

Axisymmetric, stationary collisionless gas configurations surrounding black holes

Carlos Gabarrete·Olivier Sarbach
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Abstract

The properties of a stationary gas cloud surrounding a black hole are discussed, assuming that the gas consists of collisionless, identical massive particles that follow spatially bound geodesic orbits in the Schwarzschild spacetime. Several models for the one-particle distribution function are considered, and the essential formulae that describe the relevant macroscopic observables, like the current density four-vector and the stress-energy-momentum tensor are derived. This is achieved by rewriting these observables as integrals over the constants of motion and by a careful analysis of the range of integration. In particular, we provide configurations with finite total mass and angular momentum. Differences between these configurations and their nonrelativistic counterparts in a Newtonian potential are analyzed. Finally, our configurations are compared to their hydrodynamic analogues, the "polish doughnuts".

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Carlos Gabarrete, Olivier Sarbach. 2022-09-12. Axisymmetric, stationary collisionless gas configurations surrounding black holes. https://doi.org/10.1088/1361-6382%2Facb193

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