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Title: Chiral primordial blue tensor spectra from the axion-gauge couplings

Abstract

We suggest the new feature of primordial gravitational waves sourced by the axion-gauge couplings, whose forms are motivated by the dimensional reduction of the form field in the string theory. In our inflationary model, as an inflaton we adopt two types of axion, dubbed the model-independent axion and the model-dependent axion, which couple with two gauge groups with different sign combination each other. Due to these forms both polarization modes of gauge fields are amplified and enhance both helicies of tensor modes during inflation. We point out the possibility that a primordial blue-tilted tensor power spectra with small chirality are provided by the combination of these axion-gauge couplings, intriguingly both amplitudes and chirality are potentially testable by future space-based gravitational wave interferometers such as DECIGO and BBO project.

Authors:
 [1]
  1. Department of Physics, Kyoto University, Kyoto, 606-8502 (Japan)
Publication Date:
OSTI Identifier:
22676137
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; AMPLITUDES; AXIONS; CHIRALITY; COUPLING; GRAVITATIONAL WAVES; INFLATIONARY UNIVERSE; INFLATONS; INTERFEROMETERS; POLARIZATION; SPACE; SPECTRA; STRING THEORY

Citation Formats

Obata, Ippei, E-mail: obata@tap.scphys.kyoto-u.ac.jp. Chiral primordial blue tensor spectra from the axion-gauge couplings. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/06/050.
Obata, Ippei, E-mail: obata@tap.scphys.kyoto-u.ac.jp. Chiral primordial blue tensor spectra from the axion-gauge couplings. United States. doi:10.1088/1475-7516/2017/06/050.
Obata, Ippei, E-mail: obata@tap.scphys.kyoto-u.ac.jp. Thu . "Chiral primordial blue tensor spectra from the axion-gauge couplings". United States. doi:10.1088/1475-7516/2017/06/050.
@article{osti_22676137,
title = {Chiral primordial blue tensor spectra from the axion-gauge couplings},
author = {Obata, Ippei, E-mail: obata@tap.scphys.kyoto-u.ac.jp},
abstractNote = {We suggest the new feature of primordial gravitational waves sourced by the axion-gauge couplings, whose forms are motivated by the dimensional reduction of the form field in the string theory. In our inflationary model, as an inflaton we adopt two types of axion, dubbed the model-independent axion and the model-dependent axion, which couple with two gauge groups with different sign combination each other. Due to these forms both polarization modes of gauge fields are amplified and enhance both helicies of tensor modes during inflation. We point out the possibility that a primordial blue-tilted tensor power spectra with small chirality are provided by the combination of these axion-gauge couplings, intriguingly both amplitudes and chirality are potentially testable by future space-based gravitational wave interferometers such as DECIGO and BBO project.},
doi = {10.1088/1475-7516/2017/06/050},
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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