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Title: Reheating dynamics affects non-perturbative decay of spectator fields

Abstract

The behaviour of oscillating scalar spectator fields after inflation depends on the thermal background produced by inflaton decay. Resonant decay of the spectator is often blocked by large induced thermal masses. We account for the finite decay width of the inflaton and the protracted build-up of the thermal bath to determine the early evolution of a homogeneous spectator field σ coupled to the Higgs Boson Φ through the term g{sup 2}σ{sup 2}Φ{sup 2}, the only renormalisable coupling of a new scalar to the Standard Model. We find that for very large higgs-spectator coupling g∼>10{sup −3}, the resonance is not always blocked as was previously suggested. As a consequence, the oscillating spectator can decay quickly. For other parameter values, we find that although qualitative features of the thermal blocking still hold, the dynamics are altered compared to the instant decay case. These findings are important for curvaton models, where the oscillating field must be relatively long lived in order to produce the curvature perturbation. They are also relevant for other spectator fields, which must decay sufficiently early to avoid spoiling the predictions of baryogenesis and nucleosynthesis.

Authors:
; ;  [1]
  1. University of Helsinki and Helsinki Institute of Physics, P.O. Box 64, FI-00014, Helsinki (Finland)
Publication Date:
OSTI Identifier:
22369923
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2013; Journal Issue: 11; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COUPLING; HIGGS BOSONS; HIGGS MODEL; NUCLEOSYNTHESIS; PARTICLE DECAY; PERTURBATION THEORY; SCALAR FIELDS; STANDARD MODEL

Citation Formats

Enqvist, Kari, Lerner, Rose N., and Rusak, Stanislav, E-mail: kari.enqvist@helsinki.fi, E-mail: rose.lerner@helsinki.fi, E-mail: stanislav.rusak@helsinki.fi. Reheating dynamics affects non-perturbative decay of spectator fields. United States: N. p., 2013. Web. doi:10.1088/1475-7516/2013/11/034.
Enqvist, Kari, Lerner, Rose N., & Rusak, Stanislav, E-mail: kari.enqvist@helsinki.fi, E-mail: rose.lerner@helsinki.fi, E-mail: stanislav.rusak@helsinki.fi. Reheating dynamics affects non-perturbative decay of spectator fields. United States. doi:10.1088/1475-7516/2013/11/034.
Enqvist, Kari, Lerner, Rose N., and Rusak, Stanislav, E-mail: kari.enqvist@helsinki.fi, E-mail: rose.lerner@helsinki.fi, E-mail: stanislav.rusak@helsinki.fi. 2013. "Reheating dynamics affects non-perturbative decay of spectator fields". United States. doi:10.1088/1475-7516/2013/11/034.
@article{osti_22369923,
title = {Reheating dynamics affects non-perturbative decay of spectator fields},
author = {Enqvist, Kari and Lerner, Rose N. and Rusak, Stanislav, E-mail: kari.enqvist@helsinki.fi, E-mail: rose.lerner@helsinki.fi, E-mail: stanislav.rusak@helsinki.fi},
abstractNote = {The behaviour of oscillating scalar spectator fields after inflation depends on the thermal background produced by inflaton decay. Resonant decay of the spectator is often blocked by large induced thermal masses. We account for the finite decay width of the inflaton and the protracted build-up of the thermal bath to determine the early evolution of a homogeneous spectator field σ coupled to the Higgs Boson Φ through the term g{sup 2}σ{sup 2}Φ{sup 2}, the only renormalisable coupling of a new scalar to the Standard Model. We find that for very large higgs-spectator coupling g∼>10{sup −3}, the resonance is not always blocked as was previously suggested. As a consequence, the oscillating spectator can decay quickly. For other parameter values, we find that although qualitative features of the thermal blocking still hold, the dynamics are altered compared to the instant decay case. These findings are important for curvaton models, where the oscillating field must be relatively long lived in order to produce the curvature perturbation. They are also relevant for other spectator fields, which must decay sufficiently early to avoid spoiling the predictions of baryogenesis and nucleosynthesis.},
doi = {10.1088/1475-7516/2013/11/034},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 11,
volume = 2013,
place = {United States},
year = 2013,
month =
}
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