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arXiv · 2204.01180

Effective treatment of U(1) gauge field and charged particles in axion inflation

Tomohiro Fujita·Jun'ya Kume·Kyohei Mukaida·Yuichiro Tada
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Abstract

The axionic inflaton with the Chern-Simons coupling may generate U(1) gauge fields and charged particles simultaneously. In order to incorporate the backreaction from the charged particles on the gauge fields, we develop a procedure to obtain an equilibrium solution for the gauge fields by treating the induced current as effective electric and magnetic conductivities. Introducing mean field approximation, and numerically solving self-consistency equations, we find that the gauge field amplitudes are drastically suppressed. Interestingly, as the production becomes more efficient, the charged particles gain a larger part of the transferred energy from the inflaton and eventually dominate it. Our formalism offers a basis to connect this class of inflationary models to a rich phenomenology such as baryogenesis and magnetogenesis.

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Tomohiro Fujita, Jun'ya Kume, Kyohei Mukaida, Yuichiro Tada. 2022-04-03. Effective treatment of U(1) gauge field and charged particles in axion inflation. https://doi.org/10.1088/1475-7516%2F2022%2F09%2F023

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