Speaker
Description
In the magnetospheres of magnetars, strongly magnetized neutron stars, the magnetic field can be tens of times the critical Schwinger field $B_Q = m^2/e \approx 4.41\cdot 10^{13}$ G. In this strong field regime quantum electrodynamics (QED) becomes nonlinear, which has profound effects on the plasma dynamics of the magnetosphere. Most notably the energies of electrons and positrons become quantized into Landau levels and scattering cross sections obtain resonances, i.e., specific energies where the interaction probability is strongly amplified. In this talk, I will present a new formalism for calculating QED scattering cross sections in strong background magnetic fields. The obtained cross sections can be used in simulations of magnetar magnetospheres with the goal of explaining the double-peak structure of magnetar emission spectra.
