Decoherence in supernova neutrino transformations suppressed by deleptonization
- AHEP Group, Institut de Fisica Corpuscular, CSIC/Universitat de Valencia, Edifici Instituts d'Investigacio, Apt. 22085, 46071 Valencia (Spain)
- Max-Planck-Institut fuer Physik (Werner-Heisenberg-Institut), Foehringer Ring 6, 80805 Munich (Germany)
- II. Institut fuer theoretische Physik, Universitaet Hamburg, Luruper Chaussee 149, D-22761 Hamburg (Germany) and APC (AstroParticules et Cosmologie), 10, rue Alice Domon et Leonie Duquet, 75205 Paris Cedex 13 (France)
In the dense-neutrino region at 50-400 km above the neutrino sphere in a supernova, neutrino-neutrino interactions cause large flavor transformations. We study when the multiangle nature of the neutrino trajectories leads to flavor decoherence between different angular modes. We consider a two-flavor mixing scenario between {nu}{sub e} and another flavor {nu}{sub x} and assume the usual hierarchy F{sub {nu}{sub e}}>F{sub {nu}{sub e}}>F{sub {nu}{sub x}}=F{sub {nu}{sub x}} for the number fluxes. We define {epsilon}=(F{sub {nu}{sub e}}-F{sub {nu}{sub e}})/(F{sub {nu}{sub e}}-F{sub {nu}{sub x}}) as a measure for the deleptonization flux which is the one crucial parameter. The transition between the quasi-single-angle behavior and multiangle decoherence is abrupt as a function of {epsilon}. For typical choices of other parameters, multiangle decoherence is suppressed for {epsilon} > or approx. 0.3, but a much smaller asymmetry suffices if the neutrino mass hierarchy is normal and the mixing angle small. The critical {epsilon} depends logarithmically on the neutrino luminosity. In a realistic supernova scenario, the deleptonization flux is probably enough to suppress multiangle decoherence.
- OSTI ID:
- 21024083
- Journal Information:
- Physical Review. D, Particles Fields, Vol. 76, Issue 12; Other Information: DOI: 10.1103/PhysRevD.76.125018; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
- Country of Publication:
- United States
- Language:
- English
Similar Records
Detectability of collective neutrino oscillation signatures in the supernova explosion of a 8.8 M⊙ star
Sterile neutrino signals from supernovae