Parametric resonance after hilltop inflation caused by an inhomogeneous inflaton field

Abstract

We study preheating after hilltop inflation where the inflaton couples to another scalar field, e.g. a right-handed sneutrino, which provides a mechanism for generating the correct initial conditions for inflation and also a decay channel for the inflaton that allows for reheating and non-thermal leptogenesis. In the presence of such a coupling, we find that after the phases of tachyonic preheating and tachyonic oscillations, during which the inflaton field becomes inhomogeneous, there can be a subsequent preheating phase where the fluctuations of the other field get resonantly enhanced, from initial vacuum fluctuations up to amplitudes of the same order (and even larger) as the ones of the inflaton field. This resonant enhancement differs from the usual parametric resonance as the inflaton field is inhomogeneous at the time the enhancement takes place. We study this effect using lattice simulations as well as semi-analytically with a generalized Floquet analysis for inhomogeneous background fields.

25 pages, 9 figures; v2: matches publication in JCAP

References in corpus (9)

• The Clustering of the SDSS DR7 Main Galaxy Sample I: A 4 per cent Distance Measure at z=0.15
• A Joint Analysis of BICEP2/Keck Array and Planck Data
• Reheating in Inflationary Cosmology: Theory and Applications
• Nonperturbative Dynamics Of Reheating After Inflation: A Review
• Stochastic growth of quantum fluctuations during slow-roll inflation
• Solving the $\eta$-Problem in Hybrid Inflation with Heisenberg Symmetry and Stabilized Modulus
• Cosmic bubble and domain wall instabilities I: parametric amplification of linear fluctuations
• Hill crossing during preheating after hilltop inflation
• Non-thermal Gravitino Production in Tribrid Inflation

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