Polarized QED cascades

By taking the spin and polarization of electrons, positrons photons into account in strong-field QED processes nonlinear Compton emission pair production, we find that growth rate cascades ultra-intense laser fields can be substantially reduced. While this means fewer particles are produced, also found them to highly polarized. We further high-energy tail particle spectra is polarized opposite expected from Sokolov-Ternov theory, which cannot explained by just spin-asymmetries production process, but results significantly "spin-straggling". employ a kinetic equation approach for electron, positron photon distributions, each spin/polarization-resolved, with effects modelled spin/polarization dependent Boltzmann-type collision operator. For photon-seeded cascades, depending on polarization, an excess or shortage early stages cascade development, provides path towards controlled experiment. Throughout paper focus rotating electric field configuration, represent idealized model allows straightforward interpretation observed effects.