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arXiv · 2108.10775

Cosmographic model of the astroparticle skies

J. Biteau·S. Marafico·Y. Kerfis·O. Deligny
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Abstract

Modeling the extragalactic astroparticle skies involves reconstructing the 3D distribution of the most extreme sources in the Universe. Full-sky tomographic surveys at near-infrared wavelengths have already enabled the astroparticle community to bind the density of sources of astrophysical neutrinos and ultra-high cosmic rays (UHECRs), constrain the distribution of binary black-hole mergers and identify some of the components of the extragalactic gamma-ray background. This contribution summarizes the efforts of cleaning and complementing the catalogs developed by the gravitational-wave and near-infrared communities, in order to obtain a cosmographic view on stellar mass ($M_*$) and star formation rate (SFR). Unprecedented cosmography is offered by a sample of about 400,000 galaxies within 350 Mpc, with a 50-50 ratio of spectroscopic and photometric distances, $M_*$, SFR and corrections for incompleteness with increasing distance and decreasing Galactic latitude. The inferred 3D distribution of $M_*$ and SFR is consistent with Cosmic Flows. The $M_*$ and SFR densities converge towards values compatible with deep-field observations beyond 100 Mpc, suggesting a close-to-isotropic distribution of more distant sources. In addition to highlighting relevant applications for the four astroparticle communities, this contribution explores the distribution of $B$-fields at Mpc scales deduced from the 3D distribution of matter, which is believed to be crucial in shaping the ultra-high-energy sky. These efforts provide a new basis for modeling UHECR anisotropies, which bodes well for the identification of their long-sought sources.

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J. Biteau, S. Marafico, Y. Kerfis, O. Deligny. 2021-08-24. Cosmographic model of the astroparticle skies. https://arxiv.org/abs/2108.10775

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