Lozanov, Kaloian D.Amin, Mustafa A.2017-08-212017-08-212016Lozanov, Kaloian D. and Amin, Mustafa A.. "The charged inflaton and its gauge fields: preheating and initial conditions for reheating." <i>Journal of Cosmology and Astroparticle Physics,</i> 2016, (2016) IOP Publishing: https://doi.org/10.1088/1475-7516/2016/06/032.https://hdl.handle.net/1911/97378We calculate particle production during inflation and in the early stages of reheating after inflation in models with a charged scalar field coupled to Abelian and non-Abelian gauge fields. A detailed analysis of the power spectra of primordial electric fields, magnetic fields and charge fluctuations at the end of inflation and preheating is provided. We carefully account for the Gauss constraints during inflation and preheating, and clarify the role of the longitudinal components of the electric field. We calculate the timescale for the back-reaction of the produced gauge fields on the inflaton condensate, marking the onset of non-linear evolution of the fields. We provide a prescription for initial conditions for lattice simulations necessary to capture the subsequent nonlinear dynamics. On the observational side, we find that the primordial magnetic fields generated are too small to explain the origin of magnetic fields on galactic scales and the charge fluctuations are well within observational bounds for the models considered in this paper.engContent from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.Journal articlecosmological perturbation theoryextragalactic magnetic fieldsinflationprimordial magnetic fieldsPreheating_initial_conditions_reheatinghttps://doi.org/10.1088/1475-7516/2016/06/032