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Title: Strong Bayesian evidence for the normal neutrino hierarchy

Abstract

The configuration of the three neutrino masses can take two forms, known as the normal and inverted hierarchies. We compute the Bayesian evidence associated with these two hierarchies. Previous studies found a mild preference for the normal hierarchy, and this was driven by the asymmetric manner in which cosmological data has confined the available parameter space. Here we identify the presence of a second asymmetry, which is imposed by data from neutrino oscillations. By combining constraints on the squared-mass splittings [1] with the limit on the sum of neutrino masses of Σ m {sub ν} < 0.13 eV [2], and using a minimally informative prior on the masses, we infer odds of 42:1 in favour of the normal hierarchy, which is classified as 'strong' in the Jeffreys' scale. We explore how these odds may evolve in light of higher precision cosmological data, and discuss the implications of this finding with regards to the nature of neutrinos. Finally the individual masses are inferred to be m {sub 1}=3.80{sup +26.2}{sub -3.73}meV; m {sub 2}=8.8{sup +18}{sub -1.2}meV; m {sub 3}=50.4{sup +5.8}{sub -1.2}meV (95% credible intervals).

Authors:
; ;  [1];  [2]
  1. ICCUB, University of Barcelona (UB-IEEC), Marti i Franques 1, Barcelona, 08028 (Spain)
  2. I2SysBio, CSIC-UVEG, P.O. 22085, Valencia, 46071 (Spain)
Publication Date:
OSTI Identifier:
22676157
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:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ASYMMETRY; COMPUTERIZED SIMULATION; CONFIGURATION; MASS; NEUTRINO OSCILLATION; NEUTRINOS; SPACE; VISIBLE RADIATION

Citation Formats

Simpson, Fergus, Jimenez, Raul, Verde, Licia, and Pena-Garay, Carlos, E-mail: fergus2@gmail.com, E-mail: raul.jimenez@icc.ub.edu, E-mail: penagaray@gmail.com, E-mail: liciaverde@icc.ub.edu. Strong Bayesian evidence for the normal neutrino hierarchy. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/06/029.
Simpson, Fergus, Jimenez, Raul, Verde, Licia, & Pena-Garay, Carlos, E-mail: fergus2@gmail.com, E-mail: raul.jimenez@icc.ub.edu, E-mail: penagaray@gmail.com, E-mail: liciaverde@icc.ub.edu. Strong Bayesian evidence for the normal neutrino hierarchy. United States. doi:10.1088/1475-7516/2017/06/029.
Simpson, Fergus, Jimenez, Raul, Verde, Licia, and Pena-Garay, Carlos, E-mail: fergus2@gmail.com, E-mail: raul.jimenez@icc.ub.edu, E-mail: penagaray@gmail.com, E-mail: liciaverde@icc.ub.edu. Thu . "Strong Bayesian evidence for the normal neutrino hierarchy". United States. doi:10.1088/1475-7516/2017/06/029.
@article{osti_22676157,
title = {Strong Bayesian evidence for the normal neutrino hierarchy},
author = {Simpson, Fergus and Jimenez, Raul and Verde, Licia and Pena-Garay, Carlos, E-mail: fergus2@gmail.com, E-mail: raul.jimenez@icc.ub.edu, E-mail: penagaray@gmail.com, E-mail: liciaverde@icc.ub.edu},
abstractNote = {The configuration of the three neutrino masses can take two forms, known as the normal and inverted hierarchies. We compute the Bayesian evidence associated with these two hierarchies. Previous studies found a mild preference for the normal hierarchy, and this was driven by the asymmetric manner in which cosmological data has confined the available parameter space. Here we identify the presence of a second asymmetry, which is imposed by data from neutrino oscillations. By combining constraints on the squared-mass splittings [1] with the limit on the sum of neutrino masses of Σ m {sub ν} < 0.13 eV [2], and using a minimally informative prior on the masses, we infer odds of 42:1 in favour of the normal hierarchy, which is classified as 'strong' in the Jeffreys' scale. We explore how these odds may evolve in light of higher precision cosmological data, and discuss the implications of this finding with regards to the nature of neutrinos. Finally the individual masses are inferred to be m {sub 1}=3.80{sup +26.2}{sub -3.73}meV; m {sub 2}=8.8{sup +18}{sub -1.2}meV; m {sub 3}=50.4{sup +5.8}{sub -1.2}meV (95% credible intervals).},
doi = {10.1088/1475-7516/2017/06/029},
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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