Coupling of neutrino beam-driven MHD waves and resonant instabilities in rotating magnetoplasmas with neutrino two-flavor oscillations

Abstract

We present an analysis of neutrino-driven magnetohydrodynamic (MHD) waves and instabilities in a rotating magnetoplasma with weak neutrino interactions. We show that neutrino-driven shear Alfv{\'e}n and oblique magnetosonic waves can be coupled by the Coriolis force, forming new wave modes affected by this force, as well as neutrino beam and two neutrino flavor oscillations. Our work extends previous theories by demonstrating that shear Alfv{\'e}n waves are influenced by neutrino effects and by identifying instabilities resulting from resonant interactions with both a streaming neutrino beam and flavor oscillations. We find that the Coriolis force, plasma density, and magnetic field strength significantly affect the profiles of instability growth rates. Such a growth rate for magnetosonic waves appears much higher than the Alfv{\'e}n wave, implying that magnetosonic waves provide a superior mechanism for energy extraction from the neutrino beam. For typical parameters relevant to the protoneutron star surface, the instability time for magnetosonic waves may vary in the range 0.09-0.14 s, which is within the predicted time of the neutrino-driven explosion (0.3 s after bounce) reported in the recent three-dimensional MHD simulations of core-collapse supernovae. Our findings may shed new light on the physical mechanisms underlying core-collapse supernovae.