Some astrophysical implications of dark matter and gas profiles in a new galaxy clusters model

V. F. Cardone; E. Piedipalumbo; C. Tortora

doi:10.1051/0004-6361:20040426

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arXiv · astro-ph/0408146

Some astrophysical implications of dark matter and gas profiles in a new galaxy clusters model

V. F. Cardone·E. Piedipalumbo·C. Tortora

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Abstract

The structure of the dark matter and the thermodynamical status of the hot gas in galaxy clusters is an interesting and widely discussed topic in modern astrophysics. Recently, Rasia et al. (2004) have proposed a new dynamical model for the mass density profile of clusters of galaxies as a result of a set of high resolution hydrodynamical simulations of structure formation. We investigate the lensing properties of this model evaluating the deflection angle, the lensing potential and the amplification of the images. We reserve particular attention to the structure and position of the critical curves in order to see whether this model is able to produce radial and tangential arcs. To this aim, we also investigate the effect of taking into account the brightest cluster galaxy in the lensing potential and the deviations from spherical symmetry mimicked by an external shear. We also analyze the implication of the gas density and temperature profiles of the Rasia et al.(2004) model on the properties of the X - ray emission and the comptonization parameter that determines the CMBR temperature decrement due to the Sunyaev - Zel'dovich effect.

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V. F. Cardone, E. Piedipalumbo, C. Tortora. 2004-08-09. Some astrophysical implications of dark matter and gas profiles in a new galaxy clusters model. https://doi.org/10.1051/0004-6361%3A20040426

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