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Searching for Baryons with Chandra

L. A. Phillips·J. P. Ostriker
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Abstract

At low redshifts, measurements of the total baryon content in stars, atomic and molecular hydrogen, and cluster gas fall a factor of two to four below the baryon density derived from observed light-element ratios and nucleosynthesis arguments. A possible hiding place for a significant fraction of the missing baryons is in the warm/hot gas at temperatures T = 10^{5}-10^{7}K. We present predictions of the contribution to the soft X-ray background from warm/hot gas emission calculated using new hydrodynamical simulations and discuss the possibility of detecting the spectral signature of this gas using the Chandra X-ray Observatory.

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L. A. Phillips, J. P. Ostriker. 2000-12-20. Searching for Baryons with Chandra. https://arxiv.org/abs/astro-ph/0012451

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