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Title: A full picture of large lepton number asymmetries of the Universe

Abstract

A large lepton number asymmetry of O(0.1−1) at present Universe might not only be allowed but also necessary for consistency among cosmological data. We show that, if a sizeable lepton number asymmetry were produced before the electroweak phase transition, the requirement for not producing too much baryon number asymmetry through sphalerons processes, forces the high scale lepton number asymmetry to be larger than about 03. Therefore a mild entropy release causing O(10-100) suppression of pre-existing particle density should take place, when the background temperature of the Universe is around T = O(10{sup −2}-10{sup 2}) GeV for a large but experimentally consistent asymmetry to be present today. We also show that such a mild entropy production can be obtained by the late-time decays of the saxion, constraining the parameters of the Peccei-Quinn sector such as the mass and the vacuum expectation value of the saxion field to be m {sub φ} ∼> O(10) TeV and φ{sub 0} ∼> O(10{sup 14}) GeV, respectively.

Authors:
 [1];  [2]
  1. Departament de Física Teòrica and IFIC, Universitat de València-CSIC, C/ Dr. Moliner, 50, Burjassot, E-46100 Spain (Spain)
  2. Department of Science Education (Physics), Chonbuk National University, 567 Baekje-daero, Jeonju, 561-756 (Korea, Republic of)
Publication Date:
OSTI Identifier:
22679892
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 04; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASYMMETRY; BARYON NUMBER; BARYONS; COSMOLOGICAL MODELS; DENSITY; ENTROPY; GEV RANGE; LEPTON NUMBER; LEPTONS; MASS; PARTICLE PRODUCTION; PHASE TRANSFORMATIONS; TEV RANGE; UNIVERSE

Citation Formats

Barenboim, Gabriela, and Park, Wan-Il, E-mail: Gabriela.Barenboim@uv.es, E-mail: wipark@jbnu.ac.kr. A full picture of large lepton number asymmetries of the Universe. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/04/048.
Barenboim, Gabriela, & Park, Wan-Il, E-mail: Gabriela.Barenboim@uv.es, E-mail: wipark@jbnu.ac.kr. A full picture of large lepton number asymmetries of the Universe. United States. doi:10.1088/1475-7516/2017/04/048.
Barenboim, Gabriela, and Park, Wan-Il, E-mail: Gabriela.Barenboim@uv.es, E-mail: wipark@jbnu.ac.kr. Sat . "A full picture of large lepton number asymmetries of the Universe". United States. doi:10.1088/1475-7516/2017/04/048.
@article{osti_22679892,
title = {A full picture of large lepton number asymmetries of the Universe},
author = {Barenboim, Gabriela and Park, Wan-Il, E-mail: Gabriela.Barenboim@uv.es, E-mail: wipark@jbnu.ac.kr},
abstractNote = {A large lepton number asymmetry of O(0.1−1) at present Universe might not only be allowed but also necessary for consistency among cosmological data. We show that, if a sizeable lepton number asymmetry were produced before the electroweak phase transition, the requirement for not producing too much baryon number asymmetry through sphalerons processes, forces the high scale lepton number asymmetry to be larger than about 03. Therefore a mild entropy release causing O(10-100) suppression of pre-existing particle density should take place, when the background temperature of the Universe is around T = O(10{sup −2}-10{sup 2}) GeV for a large but experimentally consistent asymmetry to be present today. We also show that such a mild entropy production can be obtained by the late-time decays of the saxion, constraining the parameters of the Peccei-Quinn sector such as the mass and the vacuum expectation value of the saxion field to be m {sub φ} ∼> O(10) TeV and φ{sub 0} ∼> O(10{sup 14}) GeV, respectively.},
doi = {10.1088/1475-7516/2017/04/048},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 04,
volume = 2017,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}
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