Calculation of primordial abundances of light nuclei including a heavy sterile neutrino

M.E.MOSQUERA; O. CIVITARESE

JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS

IOP PUBLISHING LTD

Lugar: Londres; Año: 2015 vol. 2015

1475-7516

We include the coupling of a heavy sterile neutrino with active neutrinos in thecalculation of primordial abundances of light-nuclei. We calculate neutrino distribution func-tions and primordial abundances, as functions depending on a renormalization of the sterileneutrino distribution function (a), the sterile neutrino mass (m s ) and the mixing angle (φ).Using the observable data, we set constrains on these parameters, which have the valuesa < 0.40, sin 2 φ ≈ 0.12 − 0.39 and m s < 70 keV at 1σ level, for a fixed value of the baryonto photon ratio. When the baryon to photon ratio is allowed to vary, its extracted valueis in agreement with the values constrained by Planck observations and by the WilkinsonMicrowave Anisotropy Probe (WMAP). It is found that the anomaly in the abundance of 7 Lipersists, in spite of the inclusion of a heavy sterile neutrino.