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arXiv · 1202.2969

CMB as a possible new tool to study the dark baryons in galaxies

F. De Paolis·G. Ingrosso·A. A. Nucita·D. Vetrugno·V. G. Gurzadyan·A. L. Kashin·H. G. Khachatryan·S. Mirzoyan·Ph. Jetzer·A. Qadir
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Abstract

Baryons constitute about 4% of our universe, but most of them are missing and we do not know where and in what form they are hidden. This constitute the so-called missing baryon problem. A possibility is that part of these baryons are hidden in galactic halos. We show how the 7-year data obtained by the WMAP satellite may be used to trace the halo of the nearby giant spiral galaxy M31. We detect a temperature asymmetry in the M31 halo along the rotation direction up to about 120 kpc. This could be the first detection of a galactic halo in microwaves and may open a new way to probe hidden baryons in these relatively less studied galactic objects using high accuracy CMB measurements.

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F. De Paolis, G. Ingrosso, A. A. Nucita, D. Vetrugno, V. G. Gurzadyan, A. L. Kashin, H. G. Khachatryan, S. Mirzoyan, Ph. Jetzer, A. Qadir. 2012-02-14. CMB as a possible new tool to study the dark baryons in galaxies. https://doi.org/10.1088/1742-6596/354/1/012004

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