Self-induced conversion in dense neutrino gases: Pendulum in flavour space

@inproceedings{SHannestad2006SelfinducedCI,
  title={Self-induced conversion in dense neutrino gases: Pendulum in flavour space},
  author={S.Hannestad and G.G.Raffelt and G.Sigl and Y.Y.Y.Wong},
  year={2006}
}
Neutrino-neutrino interactions can lead to collective flavour conversion effects in supernovae and in the early universe. We demonstrate that the case of"bipolar"oscillations, where a dense gas of neutrinos and antineutrinos in equal numbers completely converts from one flavour to another even if the mixing angle is small, is equivalent to a pendulum in flavour space. Bipolar flavour conversion corresponds to the swinging of the pendulum, which begins in an unstable upright position (the… 
Damping the neutrino flavor pendulum by breaking homogeneity
The most general case of self-induced neutrino flavor evolution is described by a set of kinetic equations for a dense neutrino gas evolving both in space and time. Solutions of these equations have
Self-induced decoherence in dense neutrino gases
Dense neutrino gases exhibit collective oscillations where 'self-maintained coherence' is a characteristic feature, i.e., neutrinos of different energies oscillate with the same frequency. In a
Self-induced flavor conversion of supernova neutrinos on small scales
Self-induced flavor conversion of supernova (SN) neutrinos is a generic feature of neutrino-neutrino dispersion. The corresponding run-away modes in flavor space can spontaneously break the original
Spectral swaps in a two-dimensional neutrino ring model
Neutrinos emitted deep within a supernova explosion experience a self-induced index of refraction. In the stationary, one-dimensional (1D) supernova "bulb model", this self-induced refraction can
Nonstandard neutrino self-interactions in a supernova and fast flavor conversions
We study the effects of non-standard self-interactions (NSSI) of neutrinos streaming out of a core-collapse supernova. We show that with NSSI, the standard linear stability analysis gives rise to
Self-induced neutrino flavor conversion without flavor mixing
Neutrino-neutrino refraction in dense media can cause self-induced flavor conversion triggered by collective run-away modes of the interacting flavor oscillators. The growth rates were usually found
Self-induced temporal instability from a neutrino antenna
It has been recently shown that the flavor composition of a self-interacting neutrino gas can spontaneously acquire a time-dependent pulsating component during its flavor evolution. In this work, we
Collective neutrino flavor transitions in supernovae and the role of trajectory averaging
Non-linear effects on supernova neutrino oscillations, associated with neutrino–neutrino interactions, are known to induce collective flavor transformations near the supernova core for . In scenarios
Another look at synchronized neutrino oscillations
Flavor isospin waves in one-dimensional axisymmetric neutrino gases
Flavor oscillations can occur on very short spatial and temporal scales in the dense neutrino media in a core-collapse supernova (CCSN) or binary neutron star merger (BNSM) event. Although the
...
...