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Clusters of galaxies: a fundamental pillar of cosmology

Africa Castillo-Morales·Sabine Schindler
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Abstract

Clusters of galaxies are used in a variety of ways to do cosmology. Some of them are presented here. Their X-ray emitting gas allows us to determine the baryon fraction, dark matter distribution and the matter density $Ω_{m}$ of the universe. Another interesting component is relativistic particles whose radio emission provide the measure of the magnetic fields ($\approx μG$) in the intra-cluster medium (ICM). The observation of distant clusters of galaxies is also important for cosmology. In particular the new X-ray satellites CHANDRA and XMM yield exciting new results for galaxy cluster physics and cosmology.

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Africa Castillo-Morales, Sabine Schindler. 2003-03-27. Clusters of galaxies: a fundamental pillar of cosmology. https://arxiv.org/abs/astro-ph/0303609

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