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arXiv · 0807.4805

Reheating induced by competing decay modes

T. Charters·A. Nunes·J. P. Mimoso
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Abstract

We address the problem of studying the decay of the inflaton field $\phi$ to another scalar field $\chi$ through parametric resonance in the case of a coupling that involves several decay modes. This amounts to the presence of extra harmonic terms in the perturbation of the $\chi$ field dynamics. For the case of two frequencies we compute the geometry of the resonance regions, which is significantly altered due to the presence of non-cuspidal resonance regions associated to higher harmonics and to the emergence of instability `pockets'. We discuss the effect of this change in the efficiency of the energy transfer process for the simplest case of a coupling given by a combination of the two interaction terms of homogeneous degree usually considered in the literature. We find that the presence of higher harmonics has limited cosmological implications.

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T. Charters, A. Nunes, J. P. Mimoso. 2008-07-30. Reheating induced by competing decay modes. https://doi.org/10.1103/physrevd.78.083539

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