Astronomy & Astrophysics Seminar: Fast Radio Bursts from Monster Shocks in Magnetar Flares

Zoom: https://tau-ac-il.zoom.us/j/81239615480?pwd=qynx9sGBcqWlo2fNUEbZrq1VibGgwM.1

Abstract:

Fast Radio Bursts (FRBs) are extremely short, intense flashes of radio waves originating at extragalactic distances. They exhibit a wide range of unusual properties, offering a unique opportunity to probe plasma physics in previously unexplored regimes. There is compelling evidence that at least some FRBs originate from strongly magnetized neutron stars, likely triggered by the sudden release of magnetic stresses. Recent studies show that such eruptions can launch magnetohydrodynamic (MHD) waves that grow increasingly nonlinear as they propagate through the magnetosphere, eventually steepening into a novel class of monster shocks. In this talk, after a brief overview of recent observations, I will discuss the magnetar model for FRBs, focusing in particular on the monster-shock mechanism. I will present recent particle-in-cell (PIC) simulations demonstrating that these shocks generate an intense precursor electromagnetic wave, potentially explaining a subclass of FRBs. I will also briefly discuss the underlying physics of these shocks, showing that shock dissipation is associated with the onset of chaos within a nonlinear solitary structure that forms at the shock front.

Seminar Organizer: Dr. Jonathan Stern