High-energy neutrinos from powerful radio galaxies

In order to explore mechanisms for the production of radio lobes from radio galaxies, observational tests involving neutrinos at E equal to or greater than 4 TeV are proposed. Among the mechanisms that have been suggested are: an explosive burst of energy that has been stored in or near the galactic nucleus; diffusive escape of particles from the vicinity of the galactic nucleus into plasmons; a beam from the galactic core that interacts with the circumgalactic medium; and black holes or spinars ejected from the galactic nucleus by a gravitational slingshot mechanism. As an example, neutrino fluxes from Cen A are estimated. The annual neutrino event rate at energies above 4 TeV is about 100-1000 for a DUMAND-type detector if relativistic particles are temporarily stored near the galactic nucleus, and if these have a differential energy spectrum with exponent -2.0. With a similar exponent, but allowing free escape from the galaxy, the fluxes are about 10 times lower