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Multi-phase Hydrodynamics and X-ray Clusters Formation

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 نشر من قبل Romain Teyssier
 تاريخ النشر 1997
  مجال البحث فيزياء
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 تأليف Romain Teyssier




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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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