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Title: Dark matter from gravitational particle production at reheating

Abstract

We show that curvature induced particle production at reheating generates adiabatic dark matter if there are non-minimally coupled spectator scalars weakly coupled to visible matter. The observed dark matter abundance implies an upper bound on spectator masses m and non-minimal coupling values ξ. For example, assuming quadratic inflation, instant reheating and a single spectator scalar with only gravitational couplings, the observed dark matter abundance is obtained for m ∼ 0.1 GeV and ξ ∼ 1. Larger mass and coupling values of the spectator are excluded as they would lead to overproduction of dark matter.

Authors:
 [1];  [2]
  1. Department of Physics, King's College London, Strand, London WC2R 2LS (United Kingdom)
  2. Department of Physics, University of Jyväskylä, P.O. Box 35, FI-40014 University of Jyväskylä (Finland)
Publication Date:
OSTI Identifier:
22680046
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 02; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABUNDANCE; COUPLING; GEV RANGE; INFLATIONARY UNIVERSE; MASS; NONLUMINOUS MATTER; PARTICLE PRODUCTION

Citation Formats

Markkanen, Tommi, and Nurmi, Sami, E-mail: tommi.markkanen@kcl.ac.uk, E-mail: sami.t.nurmi@jyu.fi. Dark matter from gravitational particle production at reheating. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/02/008.
Markkanen, Tommi, & Nurmi, Sami, E-mail: tommi.markkanen@kcl.ac.uk, E-mail: sami.t.nurmi@jyu.fi. Dark matter from gravitational particle production at reheating. United States. doi:10.1088/1475-7516/2017/02/008.
Markkanen, Tommi, and Nurmi, Sami, E-mail: tommi.markkanen@kcl.ac.uk, E-mail: sami.t.nurmi@jyu.fi. Wed . "Dark matter from gravitational particle production at reheating". United States. doi:10.1088/1475-7516/2017/02/008.
@article{osti_22680046,
title = {Dark matter from gravitational particle production at reheating},
author = {Markkanen, Tommi and Nurmi, Sami, E-mail: tommi.markkanen@kcl.ac.uk, E-mail: sami.t.nurmi@jyu.fi},
abstractNote = {We show that curvature induced particle production at reheating generates adiabatic dark matter if there are non-minimally coupled spectator scalars weakly coupled to visible matter. The observed dark matter abundance implies an upper bound on spectator masses m and non-minimal coupling values ξ. For example, assuming quadratic inflation, instant reheating and a single spectator scalar with only gravitational couplings, the observed dark matter abundance is obtained for m ∼ 0.1 GeV and ξ ∼ 1. Larger mass and coupling values of the spectator are excluded as they would lead to overproduction of dark matter.},
doi = {10.1088/1475-7516/2017/02/008},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 02,
volume = 2017,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}
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