Informal Astro Talk
On UHECR origin OR Jet formation in GRBs
If Jet formation in GRBs Abstract: Two competing jet formation mechanisms for gamma-ray bursts have been widely discussed in the literature; magnetic extraction of the spin down power of a Kerr black hole, and outflow formation via neutrino annihilation in the polar region, above the horizon. These two processes are commonly treated under idealized conditions: models of Blandford-Znajek jets usually invoke the force-free limit and ignore loading of magnetic field lines, whereas models of jets driven by neutrino annihilation are usually constructed within the pure hydrodynamic limit. In general, however, both processes might be at work, and it is desirable to characterize the interplay between them. I will present semianalytic models for the formation of magnetic jets around rotating black hole, including loading of the magnetic field lines, and discuss the total power of an outflow powered both by BZ and neutrino-annihilation.