Fast radio bursts as precursor radio emission from monster shocks

          @misc{ pirsa_PIRSA:25030151,
            doi = {10.48660/25030151},
            url = {https://pirsa.org/25030151},
            author = {},
            keywords = {Strong Gravity},
            language = {en},
            title = {Fast radio bursts as precursor radio emission from monster shocks},
            publisher = {Perimeter Institute},
            year = {2025},
            month = {mar},
            note = {PIRSA:25030151 see, \url{https://pirsa.org}}
          }
          

Abstract

It has been proposed recently that the breaking of MHD waves in the inner magnetosphere of strongly magnetized neutron stars can power different types of high-energy transients. We have studied the steepening and dissipation of a strongly magnetized fast magnetosonic wave propagating in a declining background magnetic field, by means of particle-in-cell simulations that encompass MHD scales. Our analysis confirms the formation of a monster shock as $B^2-E^2$ approaches zero, that dissipates about half of the fast magnetosonic wave energy, and reveals, for the first time, the generation of a high-frequency precursor wave at the monster shock, carrying a fraction of 0.001 of the total energy dissipated at the shock. The spectrum of the precursor wave exhibits several sharp harmonic peaks, with frequencies in the GHz band under conditions anticipated in magnetars. Such signals may appear as fast radio bursts.