Spin-dependent quantum radiation reaction: On the dynamics of spinning radiating particles

In this talk I will discuss several aspects of the interplay between radiation reaction effects and the spin polarization effects for particles interacting with supercritical electromagnetic fields. Boltzmann-Vlasov-type transport equations are formulated in order to incorporate the spin degree of freedom of the charged leptons, where the spin-dependent photon emission processes in ultra-intense fields are modelled via spin-dependent collision operators. The equations for spin-polarized radiation reaction are derived by calculating the moments of the spin-polarized kinetic equations. We find the conditions under which the Sokolov-Ternov theory is applicable, and identify corrections to it. A spin-dependent Gaunt factor for a phenomenological description of spin-dependent radiation reaction effects is derived from first principles. Moreover, the relation of the kinetic description to the single-particle BMT-equation will be elaborated.