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Title: Neutrino phenomenology of very low-energy seesaw scenarios

Abstract

The standard model augmented by the presence of gauge-singlet right-handed neutrinos proves to be an ideal scenario for accommodating nonzero neutrino masses. Among the new parameters of this 'new standard model' are right-handed neutrino Majorana masses M. Theoretical prejudice points to M much larger than the electroweak symmetry breaking scale, but it has recently been emphasized that all M values are technically natural and should be explored. Indeed, M around 1-10 eV can accommodate an elegant oscillation solution to the liquid scintillator neutrino detector (LSND) anomaly, while other M values lead to several observable consequences. We consider the phenomenology of low-energy (M < or approx. 1 keV) seesaw scenarios. By exploring such a framework with three right-handed neutrinos, we can consistently fit all oscillation data--including those from LSND--while partially addressing several astrophysical puzzles, including anomalous pulsar kicks, heavy element nucleosynthesis in supernovae, and the existence of warm dark matter. In order to accomplish all of this, we find that a nonstandard cosmological scenario is required. Finally, low-energy seesaws - regardless of their relation to the LSND anomaly - can also be tested by future tritium beta-decay experiments, neutrinoless double-beta decay searches, and other observables. We estimate the sensitivity of suchmore » probes to M.« less

Authors:
; ;  [1]
  1. Northwestern University, Department of Physics and Astronomy, 2145 Sheridan Road, Evanston, Illinois 60208 (United States)
Publication Date:
OSTI Identifier:
20933206
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevD.75.013003; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; DOUBLE BETA DECAY; EV RANGE 01-10; EV RANGE 100-1000; LIQUID SCINTILLATORS; MASS; MATHEMATICAL SOLUTIONS; NEUTRINOS; NONLUMINOUS MATTER; NUCLEOSYNTHESIS; PULSARS; STANDARD MODEL; SYMMETRY BREAKING; TRITIUM

Citation Formats

Gouvea, Andre de, Jenkins, James, and Vasudevan, Nirmala. Neutrino phenomenology of very low-energy seesaw scenarios. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.013003.
Gouvea, Andre de, Jenkins, James, & Vasudevan, Nirmala. Neutrino phenomenology of very low-energy seesaw scenarios. United States. doi:10.1103/PHYSREVD.75.013003.
Gouvea, Andre de, Jenkins, James, and Vasudevan, Nirmala. Mon . "Neutrino phenomenology of very low-energy seesaw scenarios". United States. doi:10.1103/PHYSREVD.75.013003.
@article{osti_20933206,
title = {Neutrino phenomenology of very low-energy seesaw scenarios},
author = {Gouvea, Andre de and Jenkins, James and Vasudevan, Nirmala},
abstractNote = {The standard model augmented by the presence of gauge-singlet right-handed neutrinos proves to be an ideal scenario for accommodating nonzero neutrino masses. Among the new parameters of this 'new standard model' are right-handed neutrino Majorana masses M. Theoretical prejudice points to M much larger than the electroweak symmetry breaking scale, but it has recently been emphasized that all M values are technically natural and should be explored. Indeed, M around 1-10 eV can accommodate an elegant oscillation solution to the liquid scintillator neutrino detector (LSND) anomaly, while other M values lead to several observable consequences. We consider the phenomenology of low-energy (M < or approx. 1 keV) seesaw scenarios. By exploring such a framework with three right-handed neutrinos, we can consistently fit all oscillation data--including those from LSND--while partially addressing several astrophysical puzzles, including anomalous pulsar kicks, heavy element nucleosynthesis in supernovae, and the existence of warm dark matter. In order to accomplish all of this, we find that a nonstandard cosmological scenario is required. Finally, low-energy seesaws - regardless of their relation to the LSND anomaly - can also be tested by future tritium beta-decay experiments, neutrinoless double-beta decay searches, and other observables. We estimate the sensitivity of such probes to M.},
doi = {10.1103/PHYSREVD.75.013003},
journal = {Physical Review. D, Particles Fields},
number = 1,
volume = 75,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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