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J. M. Dawson (UCLA), R. Bingham (Rutherford Lab), L. O. Silva (UCLA)
In order to energize the outgoing shock and guarantee a successful supernova explosion, neutrinos must deposit about 1% of their energy in the plasma. Intense fluxes of photons and electrons can drive a whole class of plasma instabilities and deposit a significant amount of their free energy in the plasma. In the same way, ultra intense fluxes of neutrinos, released in type II supernovae and gamma-ray bursters, can drive collective longitudinal plasma modes, and transfer some of their free energy to the plasma. A wider class of plasma instabilities can also be excited by neutrinos in particular those associated with the generation of electromagnetic fields (electroweak Weibel instability). We examine the electroweak generalization of the plasma instabilities driven by neutrinos. The linear growth rates for the different instability regimes are presented, and we show that the collective mechanisms are more important than the single particle collisional processes. Estimates for the pressure increase behind the stalled shock of SNe IIa are presented, including the contribution of the collective electromagnetic modes and the anomalous plasma heating due to damping of the electrostatic modes excited by the intense neutrino wind. Our results indicate that collective neutrino-plasma interactions can play an important role in the re-energization of the stalled shock, necessary for a successful SN explosion.
Work partially supported by NSF under Contract. no. AST-9713234.
The author(s) of this abstract have provided an email address for comments about the abstract: silva@physics.ucla.edu