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Title: Dark radiation constraints on mixed Axion/Neutralino dark matter

Abstract

Recent analyses of CMB data combined with the measurement of BAO and H{sub 0} show that dark radiation — parametrized by the apparent number of additional neutrinos ΔN{sub eff} contributing to the cosmic expansion — is bounded from above by about ΔN{sub eff}∼<1.6 at 95% CL. We consider the mixed axion/neutralino cold dark matter scenario which arises in R-parity conserving supersymmetric (SUSY) models wherein the strong CP problem is solved by hadronic axions with a concommitant axion(a)/saxion(s)/axino(ã) supermultiplet. Our new results include improved calculations of thermal axion and saxion production and include effects of saxion decay to axinos and axions. We show that the above bound on ΔN{sub eff} is easily satisfied if saxions are mainly thermally produced and m{sub LSP} < m{sub ã}∼

Authors:
;  [1];  [2]
  1. Dept. of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 (United States)
  2. Instituto de Física, Universidade de São Paulo, São Paulo - SP (Brazil)
Publication Date:
OSTI Identifier:
22282843
Resource Type:
Journal Article
Journal Name:
Journal of Cosmology and Astroparticle Physics
Additional Journal Information:
Journal Volume: 2013; Journal Issue: 04; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 1475-7516
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTROPHYSICS; AXIONS; COSMOLOGY; EXPANSION; HADRONS; NEUTRALINOS; NEUTRINOS; NONLUMINOUS MATTER; OSCILLATIONS; PARITY; RELICT RADIATION; SPARTICLES; SUPERSYMMETRY; WIMPS

Citation Formats

Bae, Kyu Jung, Baer, Howard, and Lessa, Andre. Dark radiation constraints on mixed Axion/Neutralino dark matter. United States: N. p., 2013. Web. doi:10.1088/1475-7516/2013/04/041.
Bae, Kyu Jung, Baer, Howard, & Lessa, Andre. Dark radiation constraints on mixed Axion/Neutralino dark matter. United States. https://doi.org/10.1088/1475-7516/2013/04/041
Bae, Kyu Jung, Baer, Howard, and Lessa, Andre. Mon . "Dark radiation constraints on mixed Axion/Neutralino dark matter". United States. https://doi.org/10.1088/1475-7516/2013/04/041.
@article{osti_22282843,
title = {Dark radiation constraints on mixed Axion/Neutralino dark matter},
author = {Bae, Kyu Jung and Baer, Howard and Lessa, Andre},
abstractNote = {Recent analyses of CMB data combined with the measurement of BAO and H{sub 0} show that dark radiation — parametrized by the apparent number of additional neutrinos ΔN{sub eff} contributing to the cosmic expansion — is bounded from above by about ΔN{sub eff}∼<1.6 at 95% CL. We consider the mixed axion/neutralino cold dark matter scenario which arises in R-parity conserving supersymmetric (SUSY) models wherein the strong CP problem is solved by hadronic axions with a concommitant axion(a)/saxion(s)/axino(ã) supermultiplet. Our new results include improved calculations of thermal axion and saxion production and include effects of saxion decay to axinos and axions. We show that the above bound on ΔN{sub eff} is easily satisfied if saxions are mainly thermally produced and m{sub LSP} < m{sub ã}∼},
doi = {10.1088/1475-7516/2013/04/041},
url = {https://www.osti.gov/biblio/22282843}, journal = {Journal of Cosmology and Astroparticle Physics},
issn = {1475-7516},
number = 04,
volume = 2013,
place = {United States},
year = {2013},
month = {4}
}