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Title: Spontaneous baryogenesis without baryon isocurvature

Abstract

We propose a new class of spontaneous baryogenesis models that does not produce baryon isocurvature perturbations. The baryon chemical potential in these models is independent of the field value of the baryon-generating scalar, hence the scalar field fluctuations are blocked from propagating into the baryon isocurvature. We demonstrate this mechanism in simple examples where spontaneous baryogenesis is driven by a non-canonical scalar field. The suppression of the baryon isocurvature allows spontaneous baryogenesis to be compatible even with high-scale inflation.

Authors:
;  [1]
  1. SISSA and INFN Sezione di Trieste, Via Bonomea 265, 34136 Trieste (Italy)
Publication Date:
OSTI Identifier:
22680018
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; BARYONS; DISTURBANCES; FLUCTUATIONS; PARTICLE PRODUCTION; PERTURBATION THEORY; SCALAR FIELDS

Citation Formats

Simone, Andrea De, and Kobayashi, Takeshi, E-mail: andrea.desimone@sissa.it, E-mail: takeshi.kobayashi@sissa.it. Spontaneous baryogenesis without baryon isocurvature. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/02/036.
Simone, Andrea De, & Kobayashi, Takeshi, E-mail: andrea.desimone@sissa.it, E-mail: takeshi.kobayashi@sissa.it. Spontaneous baryogenesis without baryon isocurvature. United States. doi:10.1088/1475-7516/2017/02/036.
Simone, Andrea De, and Kobayashi, Takeshi, E-mail: andrea.desimone@sissa.it, E-mail: takeshi.kobayashi@sissa.it. Wed . "Spontaneous baryogenesis without baryon isocurvature". United States. doi:10.1088/1475-7516/2017/02/036.
@article{osti_22680018,
title = {Spontaneous baryogenesis without baryon isocurvature},
author = {Simone, Andrea De and Kobayashi, Takeshi, E-mail: andrea.desimone@sissa.it, E-mail: takeshi.kobayashi@sissa.it},
abstractNote = {We propose a new class of spontaneous baryogenesis models that does not produce baryon isocurvature perturbations. The baryon chemical potential in these models is independent of the field value of the baryon-generating scalar, hence the scalar field fluctuations are blocked from propagating into the baryon isocurvature. We demonstrate this mechanism in simple examples where spontaneous baryogenesis is driven by a non-canonical scalar field. The suppression of the baryon isocurvature allows spontaneous baryogenesis to be compatible even with high-scale inflation.},
doi = {10.1088/1475-7516/2017/02/036},
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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