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Title: New effects of non-standard self-interactions of neutrinos in a supernova

Abstract

Neutrino self-interactions are known to lead to non-linear collective flavor oscillations in a core-collapse supernova. We point out new possible effects of non-standard self-interactions (NSSI) of neutrinos on flavor conversions in a two-flavor framework. We show that, for a single-energy neutrino-antineutrino ensemble, a flavor instability is generated even in normal hierarchy for large enough NSSI. Using a toy model for the neutrino spectra, we show that flavor-preserving NSSI lead to pinching of spectral swaps, while flavor-violating NSSI cause swaps to develop away from a spectral crossing or even in the absence of a spectral crossing. Consequently, NSSI could give rise to collective oscillations and spectral splits even during neutronization burst, for both hierarchies.

Authors:
; ;  [1]
  1. Tata Institute of Fundamental Research, Homi Bhabha Road, Mumbai, 400005 (India)
Publication Date:
OSTI Identifier:
22676185
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 05; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANTINEUTRINOS; CONVERSION; FLAVOR MODEL; INSTABILITY; INTERACTIONS; NONLINEAR PROBLEMS; OSCILLATIONS; SPECTRA; SUPERNOVAE

Citation Formats

Das, Anirban, Dighe, Amol, and Sen, Manibrata, E-mail: anirbandas@theory.tifr.res.in, E-mail: amol@theory.tifr.res.in, E-mail: manibrata@theory.tifr.res.in. New effects of non-standard self-interactions of neutrinos in a supernova. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/05/051.
Das, Anirban, Dighe, Amol, & Sen, Manibrata, E-mail: anirbandas@theory.tifr.res.in, E-mail: amol@theory.tifr.res.in, E-mail: manibrata@theory.tifr.res.in. New effects of non-standard self-interactions of neutrinos in a supernova. United States. doi:10.1088/1475-7516/2017/05/051.
Das, Anirban, Dighe, Amol, and Sen, Manibrata, E-mail: anirbandas@theory.tifr.res.in, E-mail: amol@theory.tifr.res.in, E-mail: manibrata@theory.tifr.res.in. Mon . "New effects of non-standard self-interactions of neutrinos in a supernova". United States. doi:10.1088/1475-7516/2017/05/051.
@article{osti_22676185,
title = {New effects of non-standard self-interactions of neutrinos in a supernova},
author = {Das, Anirban and Dighe, Amol and Sen, Manibrata, E-mail: anirbandas@theory.tifr.res.in, E-mail: amol@theory.tifr.res.in, E-mail: manibrata@theory.tifr.res.in},
abstractNote = {Neutrino self-interactions are known to lead to non-linear collective flavor oscillations in a core-collapse supernova. We point out new possible effects of non-standard self-interactions (NSSI) of neutrinos on flavor conversions in a two-flavor framework. We show that, for a single-energy neutrino-antineutrino ensemble, a flavor instability is generated even in normal hierarchy for large enough NSSI. Using a toy model for the neutrino spectra, we show that flavor-preserving NSSI lead to pinching of spectral swaps, while flavor-violating NSSI cause swaps to develop away from a spectral crossing or even in the absence of a spectral crossing. Consequently, NSSI could give rise to collective oscillations and spectral splits even during neutronization burst, for both hierarchies.},
doi = {10.1088/1475-7516/2017/05/051},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 05,
volume = 2017,
place = {United States},
year = {Mon May 01 00:00:00 EDT 2017},
month = {Mon May 01 00:00:00 EDT 2017}
}
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