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arXiv · 2102.10183

Neutrinos in Astrophysics and Cosmology: Theoretical Advanced Study Institute (TASI) 2020 Lectures

Kevork N. Abazajian
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Abstract

I introduce the consequences of neutrino mass and mixing in the dense environments of the early Universe and in astrophysical environments. Thermal and matter effects are reviewed in the context of a two-neutrino formalism, with methods of extension to multiple neutrinos. The observed large neutrino mixing angles place the strongest constraint on cosmological lepton (or neutrino) asymmetries, while new sterile neutrinos provide a wealth of possible new physics, including lepton asymmetry generation as well as candidates for dark matter. I also review cosmic microwave background and large-scale structure constraints on neutrino mass and energy density. Lastly, I review how X-ray astronomy has become a branch of neutrino physics in searches for keV-scale sterile neutrino dark matter radiative decay.

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Kevork N. Abazajian. 2021-02-19. Neutrinos in Astrophysics and Cosmology: Theoretical Advanced Study Institute (TASI) 2020 Lectures. https://arxiv.org/abs/2102.10183

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