Constraints on neutrino masses from WMAP5 and BBN in the lepton asymmetric universe

Journal Article · Wed Jul 01 00:00:00 EDT 2009 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2009/07/005· OSTI ID:22273171

Shiraishi, Maresuke; Ichiki, Kiyotomo; Sugiyama, Naoshi ^[1]; Ichikawa, Kazuhide ^[2]; Yamaguchi, Masahide ^[3]

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1. Department of Physics and Astrophysics, Nagoya University, Aichi 464-8602 (Japan)
2. Department of Micro Engineering, Kyoto University, Kyoto 606-8501 (Japan)
3. Department of Physics and Mathematics, Aoyama Gakuin University, Sagamihara 229-8558 (Japan)

In this paper, we put constraints on neutrino properties such as mass m{sub ν} and degeneracy parameters ξ{sub i} from WMAP5 data and light element abundances by using a Markov chain Monte Carlo (MCMC) approach. In order to take consistently into account the effects of the degeneracy parameters, we run the Big Bang Nucleosynthesis code for each value of ξ{sub i} and the other cosmological parameters to estimate the Helium abundance, which is then used to calculate CMB anisotropy spectra instead of treating it as a free parameter. We find that the constraint on m{sub ν} is fairly robust and does not vary very much even if the lepton asymmetry is allowed, and is given by Σm{sub ν} < 1.3 eV (95%C.L.)

• OSTI ID: 22273171
• Journal Information: Journal of Cosmology and Astroparticle Physics, Vol. 2009, Issue 07; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ANISOTROPY
ASTROPHYSICS
ASYMMETRY
COSMIC NEUTRINOS
COSMOLOGY
ELEMENT ABUNDANCE
EV RANGE
HELIUM
LIMITING VALUES
MARKOV PROCESS
MONTE CARLO METHOD
NUCLEOSYNTHESIS
RELICT RADIATION
REST MASS
UNIVERSE
VISIBLE RADIATION