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arXiv · astro-ph/0606301

The density profiles of hot galactic halo gas

Steen H. Hansen·Jesper Sommer-Larsen
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Abstract

Extended gas haloes around galaxies are a ubiquitous prediction of galaxy formation scenarios. However, the density profiles of this hot halo gas is virtually unknown, although various profiles have been suggested on theoretical grounds. In order to quantitatively address the gas profile, we compare galaxies from direct cosmological simulations with analytical solutions of the underlying gas equations. We find remarkable agreement between simulations and theoretical predictions. We present an expression for this gas profile with a non-trivial dependence on the total mass profile. This expression is useful when setting up equilibrium galaxy models for numerical experiments.

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Steen H. Hansen, Jesper Sommer-Larsen. 2006-06-13. The density profiles of hot galactic halo gas. https://doi.org/10.1086/510450

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