Reheating in two-sector cosmology

Journal Article · 26 August 2019 · Journal of High Energy Physics (Online)

DOI: https://doi.org/10.1007/jhep08(2019)151 · OSTI ID:1612758

Adshead, Peter ^[1]; Ralegankar, Pranjal ^[2]; Shelton, Jessie ^[2]

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1. Univ. of Illinois at Urbana-Champaign, IL (United States); DOE/OSTI
2. Univ. of Illinois at Urbana-Champaign, IL (United States)

We analyze reheating scenarios where a hidden sector is populated during reheating along with the sector containing the Standard Model. We numerically solve the Boltzmann equations describing perturbative reheating of the two sectors, including the full dependence on quantum statistics, and study how quantum statistical effects during reheating as well as the non-equilibrium inflaton-mediated energy transfer between the two sectors affects the temperature evolution of the two radiation baths. We obtain new power laws describing the temperature evolution of fermions and bosons when quantum statistics are important during reheating. We show that inflaton-mediated scattering is generically most important at radiation temperatures T ~ Mϕ/4, and build on this observation to obtain analytic estimates for the temperature asymmetry produced by asymmetric reheating. We find that for reheating temperatures Trh ≪ Mϕ/4, classical perturbative reheating provides an excellent approximation to the final temperature asymmetry, while for Trh ≫ Mϕ/4, inflaton-mediated scattering dominates the population of the colder sector and thus the final temperature asymmetry. We additionally present new techniques to calculate energy transfer rates between two relativistic species at different temperatures.

• Research Organization: Univ. of Illinois at Urbana-Champaign, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC)
• Grant/Contract Number: SC0017840
• OSTI ID: 1612758
• Journal Information: Journal of High Energy Physics (Online), Journal Name: Journal of High Energy Physics (Online) Journal Issue: 8 Vol. 2019; ISSN 1029-8479
• Publisher: Springer BerlinCopyright Statement
• Country of Publication: United States
• Language: English