Spillway Preheating

TL;DR

The paper introduces 'spillway preheating', a novel mechanism that significantly enhances energy transfer from the inflaton to radiation by utilizing fast decay of produced particles, improving preheating efficiency.

Contribution

It proposes a new particle production mechanism that boosts energy depletion during preheating by orders of magnitude through perturbative decays, extending the effectiveness of resonance.

Findings

Energy depletion can be increased by up to four orders of magnitude.

The remaining inflaton energy scales inversely with a power law.

Spillway preheating is a more efficient energy dissipation process.

Abstract

In traditional models only an order one fraction of energy is transferred from the inflaton to radiation through nonperturbative resonance production in preheating immediately after inflation, due to backreaction effects. We propose a particle production mechanism that could improve the depletion of the inflaton energy density by up to four orders of magnitude. The improvement comes from the fast perturbative decays of resonantly produced daughter particles. They act as a "spillway" to drain these daughter particles, reducing their backreaction on the inflaton and keeping the resonant production effective for a longer period. Thus we dub the scenario "spillway preheating". We also show that the fraction of energy density remaining in the inflaton has a simple inverse power-law scaling in the scenario. In general, spillway preheating is a much more efficient energy dissipation mechanism, which may have other applications in model building for particle physics.