TY  - JOUR
AU  - Vincent, A. C.
AU  - Fernandez Martinez, E.
AU  - Hernandez, P.
AU  - Mena, O.
AU  - Lattanzi, M.
PY  - 2015
DA  - 2015//
TI  - Revisiting cosmological bounds on sterile neutrinos
T2  - J. Cosmol. Astropart. Phys.
JO  - Journal of Cosmology and Astroparticle Physics
SP  - 006
EP  - 23pp
VL  - 04
IS  - 4
PB  - Iop Publishing Ltd
KW  - particle physics – cosmology connection
KW  - cosmological neutrinos
KW  - cosmology of theories beyond the SM
AB  - We employ state-of-the art cosmological observables including supernova surveys and BAO information to provide constraints on the mass and mixing angle of a non-resonantly produced sterile neutrino species, showing that cosmology can effectively rule out sterile neutrinos which decay between BBN and the present day. The decoupling of an additional heavy neutrino species can modify the time dependence of the Universe's expansion between BBN and recombination and, in extreme cases, lead to an additional matter-dominated period; while this could naively lead to a younger Universe with a larger Hubble parameter, it could later be compensated by the extra radiation expected in the form of neutrinos from sterile decay. However, recombination-era observables including the Cosmic Microwave Background (CMB), the shift parameter R-CMB and the sound horizon r(s) from Baryon Acoustic Oscillations (BAO) severely constrain this scenario. We self-consistently include the full time-evolution of the coupled sterile neutrino and standard model sectors in an MCMC, showing that if decay occurs after BBN, the sterile neutrino is essentially bounded by the constraint sin(2) theta less than or similar to 0.026(m(s)/eV)(-2).
SN  - 1475-7516
UR  - http://arxiv.org/abs/1408.1956
UR  - https://doi.org/10.1088/1475-7516/2015/04/006
DO  - 10.1088/1475-7516/2015/04/006
LA  - English
N1  - WOS:000355742500007
ID  - Vincent_etal2015
ER  -