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The structure of the ICM from High Resolution SPH simulations

G. Yepes·Y. Ascasibar·R. Sevilla·S. Gottlober·V. Muller
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Abstract

We present results from a set of high (512^3 effective resolution), and ultra-high (1024^3) SPH adiabatic cosmological simulations of cluster formation aimed at studying the internal structure of the intracluster medium (ICM). We derive a self-consistent analytical model of the structure of the intracluster medium (ICM). We discuss the radial structure and scaling relations expected from purely gravitational collapse, and show that the choice of a particular halo model can have important consequences on the interpretation of observational data. The validity of the approximations of hydrostatic equilibrium and a polytropic equation of state are checked against results of our simulations. The properties of the ICM are fully specified when a 'universal' profile is assumed for either the dark or the baryonic component. We also show the first results from an unprecedented large-scale simulation of 500 Mpc/h and 2 times 512^3 gas and dark matter particles. This experiment will make possible a detailed study of the large-scale distribution of clusters as a function of their X-ray properties.

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G. Yepes, Y. Ascasibar, R. Sevilla, S. Gottlober, V. Muller. 2004-04-28. The structure of the ICM from High Resolution SPH simulations. https://doi.org/10.1017/s1743921304000584

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