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arXiv · hep-ph/9608458

The Universe after inflation: the wide resonance case

S. Yu. Khlebnikov·I. I. Tkachev
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Abstract

We study numerically the decay of massive and massless inflatons into massive excitations, via a $ϕ^2 X^2$ coupling, in the expanding Universe. We find that a wide enough resonance can survive the Universe expansion, though account for the expansion is very important for determining precisely how wide it should be. For a massive inflaton, the effective production of particles with mass ten times that of the inflaton requires very large values of the resonance parameter $q$, $q\gsim 10^8$. For these large $q$, the maximal size of produced fluctuations is significantly suppressed by the back reaction, but at least within the Hartree approximation they are still not negligible. For the massless inflaton with a $λϕ^4/4$ potential, the Universe expansion completely prevents a resonance production of particles with masses larger than $\sqrtλϕ(0)$ for $q$ up to $q=10^6$.

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S. Yu. Khlebnikov, I. I. Tkachev. 1996-08-27. The Universe after inflation: the wide resonance case. https://doi.org/10.1016/s0370-2693(96)01419-0

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