Aspects of neutrino oscillation in alternative gravity theories
Abstract
Neutrino spin and flavour oscillation in curved spacetime have been studied for the most general static spherically symmetric configuration. Having exploited the spherical symmetry we have confined ourselves to the equatorial plane in order to determine the spin and flavour oscillation frequency in this general setup. Using the symmetry properties we have derived spin oscillation frequency for neutrino moving along a geodesic or in a circular orbit. Starting from the expression of neutrino spin oscillation frequency we have shown that even in this general context, in high energy limit the spin oscillation frequency for neutrino moving along circular orbit vanishes. We have verified previous results along this line by transforming to Schwarzschild coordinates under appropriate limit. This finally lends itself to the probability of neutrino helicity flip which turns out to be nonzero. While for neutrino flavour oscillation we have derived general results for oscillation phase, which subsequently have been applied to three different gravity theories. One, of them appears as lowenergy approximation to string theory, where we have an additional field, namely, dilaton field coupled to Maxwell field tensor. This yields a realization of ReissnerNordström solution in string theory at lowenergy. Next one corresponds to generalization of Schwarzschild solutionmore »
 Authors:

 IUCAA, Post Bag 4, Ganeshkhind, Pune University Campus, Pune 411 007 (India)
 Publication Date:
 OSTI Identifier:
 22525282
 Resource Type:
 Journal Article
 Journal Name:
 Journal of Cosmology and Astroparticle Physics
 Additional Journal Information:
 Journal Volume: 2015; Journal Issue: 10; Other Information: Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 14757516
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BLACK HOLES; FLAVOR MODEL; GRAVITATION; HELICITY; MATHEMATICAL SOLUTIONS; NEUTRINO OSCILLATION; ORBITS; PROBABILITY; SCHWARZSCHILD METRIC; SOLAR NEUTRINOS; SPACETIME; SPHERICAL CONFIGURATION; SPIN; STRING THEORY; TENSORS
Citation Formats
Chakraborty, Sumanta. Aspects of neutrino oscillation in alternative gravity theories. United States: N. p., 2015.
Web. doi:10.1088/14757516/2015/10/019.
Chakraborty, Sumanta. Aspects of neutrino oscillation in alternative gravity theories. United States. https://doi.org/10.1088/14757516/2015/10/019
Chakraborty, Sumanta. Thu .
"Aspects of neutrino oscillation in alternative gravity theories". United States. https://doi.org/10.1088/14757516/2015/10/019.
@article{osti_22525282,
title = {Aspects of neutrino oscillation in alternative gravity theories},
author = {Chakraborty, Sumanta},
abstractNote = {Neutrino spin and flavour oscillation in curved spacetime have been studied for the most general static spherically symmetric configuration. Having exploited the spherical symmetry we have confined ourselves to the equatorial plane in order to determine the spin and flavour oscillation frequency in this general setup. Using the symmetry properties we have derived spin oscillation frequency for neutrino moving along a geodesic or in a circular orbit. Starting from the expression of neutrino spin oscillation frequency we have shown that even in this general context, in high energy limit the spin oscillation frequency for neutrino moving along circular orbit vanishes. We have verified previous results along this line by transforming to Schwarzschild coordinates under appropriate limit. This finally lends itself to the probability of neutrino helicity flip which turns out to be nonzero. While for neutrino flavour oscillation we have derived general results for oscillation phase, which subsequently have been applied to three different gravity theories. One, of them appears as lowenergy approximation to string theory, where we have an additional field, namely, dilaton field coupled to Maxwell field tensor. This yields a realization of ReissnerNordström solution in string theory at lowenergy. Next one corresponds to generalization of Schwarzschild solution by introduction of quadratic curvature terms of all possible form to the EinsteinHilbert action. Finally, we have also discussed regular black hole solutions. In all these cases the flavour oscillation probabilities can be determined for solar neutrinos and thus can be used to put bounds on the parameters of these gravity theories. While for spin oscillation probability, we have considered two cases, GaussBonnet term added to the EinsteinHilbert action and the f(R) gravity theory. In both these cases we could impose bounds on the parameters which are consistent with previous considerations. In a nutshell, in this work we have presented both spin and flavour oscillation frequency of neutrino in most general static spherically symmetric spacetime, encompassing a vast class of solutions, which when applied to three such instances in alternative theories for flavour oscillation and two alternative theories for spin oscillation put bounds on the parameters of these theories. Implications are also discussed.},
doi = {10.1088/14757516/2015/10/019},
url = {https://www.osti.gov/biblio/22525282},
journal = {Journal of Cosmology and Astroparticle Physics},
issn = {14757516},
number = 10,
volume = 2015,
place = {United States},
year = {2015},
month = {10}
}