Dark matter relics and the expansion rate in scalartensor theories
Abstract
We study the impact of a modified expansion rate on the dark matter relic abundance in a class of scalartensor theories. The scalartensor theories we consider are motivated from string theory constructions, which have conformal as well as disformally coupled matter to the scalar. We investigate the effects of such a conformal coupling to the dark matter relic abundance for a wide range of initial conditions, masses and crosssections. We find that exploiting all possible initial conditions, the annihilation crosssection required to satisfy the dark matter content can differ from the thermal average crosssection in the standard case. We also study the expansion rate in the disformal case and find that physically relevant solutions require a nontrivial relation between the conformal and disformal functions. We study the effects of the disformal coupling in an explicit example where the disformal function is quadratic.
 Authors:
 Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States)
 Department of Physics, Swansea University, Singleton Park, Swansea, SA2 8PP (United Kingdom)
 Publication Date:
 OSTI Identifier:
 22676152
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 06; 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; ABUNDANCE; ANNIHILATION; COMPUTERIZED SIMULATION; COUPLING; CROSS SECTIONS; EXPANSION; FIELD THEORIES; MASS; MATHEMATICAL SOLUTIONS; NONLUMINOUS MATTER; STRING THEORY
Citation Formats
Dutta, Bhaskar, Jimenez, Esteban, and Zavala, Ivonne, Email: dutta@physics.tamu.edu, Email: este1985@physics.tamu.edu, Email: e.i.zavalacarrasco@swansea.ac.uk. Dark matter relics and the expansion rate in scalartensor theories. United States: N. p., 2017.
Web. doi:10.1088/14757516/2017/06/032.
Dutta, Bhaskar, Jimenez, Esteban, & Zavala, Ivonne, Email: dutta@physics.tamu.edu, Email: este1985@physics.tamu.edu, Email: e.i.zavalacarrasco@swansea.ac.uk. Dark matter relics and the expansion rate in scalartensor theories. United States. doi:10.1088/14757516/2017/06/032.
Dutta, Bhaskar, Jimenez, Esteban, and Zavala, Ivonne, Email: dutta@physics.tamu.edu, Email: este1985@physics.tamu.edu, Email: e.i.zavalacarrasco@swansea.ac.uk. Thu .
"Dark matter relics and the expansion rate in scalartensor theories". United States.
doi:10.1088/14757516/2017/06/032.
@article{osti_22676152,
title = {Dark matter relics and the expansion rate in scalartensor theories},
author = {Dutta, Bhaskar and Jimenez, Esteban and Zavala, Ivonne, Email: dutta@physics.tamu.edu, Email: este1985@physics.tamu.edu, Email: e.i.zavalacarrasco@swansea.ac.uk},
abstractNote = {We study the impact of a modified expansion rate on the dark matter relic abundance in a class of scalartensor theories. The scalartensor theories we consider are motivated from string theory constructions, which have conformal as well as disformally coupled matter to the scalar. We investigate the effects of such a conformal coupling to the dark matter relic abundance for a wide range of initial conditions, masses and crosssections. We find that exploiting all possible initial conditions, the annihilation crosssection required to satisfy the dark matter content can differ from the thermal average crosssection in the standard case. We also study the expansion rate in the disformal case and find that physically relevant solutions require a nontrivial relation between the conformal and disformal functions. We study the effects of the disformal coupling in an explicit example where the disformal function is quadratic.},
doi = {10.1088/14757516/2017/06/032},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 06,
volume = 2017,
place = {United States},
year = {Thu Jun 01 00:00:00 EDT 2017},
month = {Thu Jun 01 00:00:00 EDT 2017}
}

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