Effective treatment of U(1) gauge field and charged particles in axion inflation. Issue 9 (1st September 2022)

• Record Type: Journal Article
• Authors: Fujita, Tomohiro; Kume, Jun'ya; Mukaida, Kyohei; Tada, Yuichiro
• Is Part Of: Journal of cosmology and astroparticle physics. Volume 2022:Issue 9(2022)
• Publication Date: 2022-09-01
• Subjects: particle physics - cosmology connection -- inflation -- primordial magnetic fields; Cosmology -- Periodicals; Astrophysics -- Periodicals; 523.0105
• DOI: 10.1088/1475-7516/2022/09/023
• Languages: English
• ISSNs: 1475-7516

Abstract

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.