Post-Reheating Inflaton Production as a Probe of Reheating Dynamics
Abstract
Cosmological reheating bridges the inflationary epoch and the hot big bang phase, yet its underlying dynamics remain poorly understood. In this work, we investigate a minimal scenario in which the inflaton evolves under a simple power-law potential during reheating and interacts with other particles via renormalizable couplings. We show that inflaton quanta can be regenerated from the thermal bath even after the decay of the coherent inflaton field, unveiling a previously overlooked channel for inflaton particle production, which offers a novel window into probing reheating. Remarkably, this mechanism may also account for the observed dark matter abundance, providing a natural link between early Universe dynamics and present-day cosmological observations.
Cite
@article{arxiv.2508.20402,
title = {Post-Reheating Inflaton Production as a Probe of Reheating Dynamics},
author = {Kunio Kaneta and Tomo Takahashi and Natsumi Watanabe},
journal= {arXiv preprint arXiv:2508.20402},
year = {2025}
}
Comments
6 pages, 2 figures, discussion on meson-decay measurements is revised, conclusion does not change