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Multi-phase Hydrodynamics and X-ray Clusters Formation

Romain Teyssier·Jean-Pierre CHIEZE·Jean-Michel Alimi
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Abstract

We investigate the role of radiative cooling within the core of large X-ray clusters using multi-phase hydrodynamics. We developed for that purpose a spherically symmetric hydrodynamical code, coupled to a "fluid model" that describes accurately the dark matter component. Cooling is included using a self-consistent multi-phase approach, leading to "cooled gas" mass deposition throughout the flow. We simulate the collapse and the subsequent evolution of a Coma-like X-ray cluster, avoiding the well-known "cooling catastrophe". The total mass profile of our simulated cluster is very similar to the "universal" profile proposed by Navarro, Frenk & White (1995). More interestingly, we also obtain a quasi-isothermal temperature profile, which is a direct consequence of multi-phase cooling within such a potential well.

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Romain Teyssier, Jean-Pierre CHIEZE, Jean-Michel Alimi. 1997-10-01. Multi-phase Hydrodynamics and X-ray Clusters Formation. https://arxiv.org/abs/astro-ph/9710010

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