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Anisotropy of the Cosmic Neutrino Background

R. J. Michney·R. R. Caldwell
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Abstract

The cosmic neutrino background (CNB) consists of low-energy relic neutrinos which decoupled from the cosmological fluid at a redshift z ~ 10^{10}. Despite being the second-most abundant particles in the universe, direct observation remains a distant challenge. Based on the measured neutrino mass differences, one species of neutrinos may still be relativistic with a thermal distribution characterized by the temperature T ~ 1.9K. We show that the temperature distribution on the sky is anisotropic, much like the photon background, experiencing Sachs-Wolfe and integrated Sachs-Wolfe effects.

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R. J. Michney, R. R. Caldwell. 2006-09-12. Anisotropy of the Cosmic Neutrino Background. https://doi.org/10.1088/1475-7516%2F2007%2F01%2F014

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