Gravitational wave production from preheating: parameter dependence
Abstract
Parametric resonance is among the most efficient phenomena generating gravitational waves (GWs) in the early Universe. The dynamics of parametric resonance, and hence of the GWs, depend exclusively on the resonance parameter q . The latter is determined by the properties of each scenario: the initial amplitude and potential curvature of the oscillating field, and its coupling to other species. Previous works have only studied the GW production for fixed value(s) of q . We present an analytical derivation of the GW amplitude dependence on q , valid for any scenario, which we confront against numerical results. By running lattice simulations in an expanding grid, we study for a wide range of q values, the production of GWs in postinflationary preheating scenarios driven by parametric resonance. We present simple fits for the final amplitude and position of the local maxima in the GW spectrum. Our parametrization allows to predict the location and amplitude of the GW background today, for an arbitrary q . The GW signal can be rather large, as h {sup 2Ω}{sub GW}( f {sub p} ) ∼< 10{sup −11}, but it is always peaked at high frequencies f {sub p} ∼> 10{sup 7} Hz. We also discussmore »
 Authors:
 Theory Division, CERN, 1211 Geneva (Switzerland)
 Instituto de Física Teórica IFTUAM/CSIC, Universidad Autónoma de Madrid, Cantoblanco 28049 Madrid, Spain. (Spain)
 Publication Date:
 OSTI Identifier:
 22667611
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 10; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AMPLITUDES; COMPUTERIZED SIMULATION; COUPLING; GRAVITATIONAL WAVES; HEAT TREATMENTS; HIGGS BOSONS; HIGGS MODEL; QVALUE; RESONANCE; SPECTRA; STANDARD MODEL; UNIVERSE
Citation Formats
Figueroa, Daniel G., and Torrentí, Francisco, Email: daniel.figueroa@cern.ch, Email: f.torrenti@csic.es. Gravitational wave production from preheating: parameter dependence. United States: N. p., 2017.
Web. doi:10.1088/14757516/2017/10/057.
Figueroa, Daniel G., & Torrentí, Francisco, Email: daniel.figueroa@cern.ch, Email: f.torrenti@csic.es. Gravitational wave production from preheating: parameter dependence. United States. doi:10.1088/14757516/2017/10/057.
Figueroa, Daniel G., and Torrentí, Francisco, Email: daniel.figueroa@cern.ch, Email: f.torrenti@csic.es. 2017.
"Gravitational wave production from preheating: parameter dependence". United States.
doi:10.1088/14757516/2017/10/057.
@article{osti_22667611,
title = {Gravitational wave production from preheating: parameter dependence},
author = {Figueroa, Daniel G. and Torrentí, Francisco, Email: daniel.figueroa@cern.ch, Email: f.torrenti@csic.es},
abstractNote = {Parametric resonance is among the most efficient phenomena generating gravitational waves (GWs) in the early Universe. The dynamics of parametric resonance, and hence of the GWs, depend exclusively on the resonance parameter q . The latter is determined by the properties of each scenario: the initial amplitude and potential curvature of the oscillating field, and its coupling to other species. Previous works have only studied the GW production for fixed value(s) of q . We present an analytical derivation of the GW amplitude dependence on q , valid for any scenario, which we confront against numerical results. By running lattice simulations in an expanding grid, we study for a wide range of q values, the production of GWs in postinflationary preheating scenarios driven by parametric resonance. We present simple fits for the final amplitude and position of the local maxima in the GW spectrum. Our parametrization allows to predict the location and amplitude of the GW background today, for an arbitrary q . The GW signal can be rather large, as h {sup 2Ω}{sub GW}( f {sub p} ) ∼< 10{sup −11}, but it is always peaked at high frequencies f {sub p} ∼> 10{sup 7} Hz. We also discuss the case of spectatorfield scenarios, where the oscillatory field can be e.g. a curvaton, or the Standard Model Higgs.},
doi = {10.1088/14757516/2017/10/057},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 10,
volume = 2017,
place = {United States},
year = 2017,
month =
}

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