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Title: Hiding an elephant: heavy sterile neutrino with large mixing angle does not contradict cosmology

Abstract

We study a model of a keV-scale sterile neutrino with a relatively large mixing with the Standard Model sector. Usual considerations predict active generation of such particles in the early Universe, which leads to constraints from the total Dark Matter density and absence of X-ray signal from sterile neutrino decay. These bounds together may deem any attempt of creation of the keV scale sterile neutrino in the laboratory unfeasible. We argue that for models with a hidden sector coupled to the sterile neutrino these bounds can be evaded, opening new perspectives for the direct studies at neutrino experiments such as Troitsk ν-mass and KATRIN. We estimate the generation of sterile neutrinos in scenarios with the hidden sector dynamics keeping the sterile neutrinos either massless or superheavy in the early Universe. In both cases the generation by oscillations from active neutrinos in plasma is suppressed.

Authors:
 [1]; ;  [2]
  1. The University of Manchester, School of Physics and Astronomy, Oxford Road, Manchester M13 9PL (United Kingdom)
  2. Institute for Nuclear Research of the Russian Academy of Sciences, 60th October Anniversary prospect 7a, Moscow 117312 (Russian Federation)
Publication Date:
OSTI Identifier:
22676134
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 06; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COSMOLOGY; DENSITY; KEV RANGE; MASS; MIXING ANGLE; NONLUMINOUS MATTER; OSCILLATIONS; PARTICLE DECAY; PLASMA; STANDARD MODEL; STERILE NEUTRINOS; UNIVERSE; X RADIATION

Citation Formats

Bezrukov, F., Chudaykin, A., and Gorbunov, D., E-mail: Fedor.Bezrukov@manchester.ac.uk, E-mail: chudy@ms2.inr.ac.ru, E-mail: gorby@ms2.inr.ac.ru. Hiding an elephant: heavy sterile neutrino with large mixing angle does not contradict cosmology. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/06/051.
Bezrukov, F., Chudaykin, A., & Gorbunov, D., E-mail: Fedor.Bezrukov@manchester.ac.uk, E-mail: chudy@ms2.inr.ac.ru, E-mail: gorby@ms2.inr.ac.ru. Hiding an elephant: heavy sterile neutrino with large mixing angle does not contradict cosmology. United States. doi:10.1088/1475-7516/2017/06/051.
Bezrukov, F., Chudaykin, A., and Gorbunov, D., E-mail: Fedor.Bezrukov@manchester.ac.uk, E-mail: chudy@ms2.inr.ac.ru, E-mail: gorby@ms2.inr.ac.ru. Thu . "Hiding an elephant: heavy sterile neutrino with large mixing angle does not contradict cosmology". United States. doi:10.1088/1475-7516/2017/06/051.
@article{osti_22676134,
title = {Hiding an elephant: heavy sterile neutrino with large mixing angle does not contradict cosmology},
author = {Bezrukov, F. and Chudaykin, A. and Gorbunov, D., E-mail: Fedor.Bezrukov@manchester.ac.uk, E-mail: chudy@ms2.inr.ac.ru, E-mail: gorby@ms2.inr.ac.ru},
abstractNote = {We study a model of a keV-scale sterile neutrino with a relatively large mixing with the Standard Model sector. Usual considerations predict active generation of such particles in the early Universe, which leads to constraints from the total Dark Matter density and absence of X-ray signal from sterile neutrino decay. These bounds together may deem any attempt of creation of the keV scale sterile neutrino in the laboratory unfeasible. We argue that for models with a hidden sector coupled to the sterile neutrino these bounds can be evaded, opening new perspectives for the direct studies at neutrino experiments such as Troitsk ν-mass and KATRIN. We estimate the generation of sterile neutrinos in scenarios with the hidden sector dynamics keeping the sterile neutrinos either massless or superheavy in the early Universe. In both cases the generation by oscillations from active neutrinos in plasma is suppressed.},
doi = {10.1088/1475-7516/2017/06/051},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 06,
volume = 2017,
place = {United States},
year = {Thu Jun 01 00:00:00 EDT 2017},
month = {Thu Jun 01 00:00:00 EDT 2017}
}
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