Self-consistent kinetic equations for $e^-e^+\gamma$-plasma generated from vacuum by strong electric field.

We present a self-consistent kinetic description of an electron-positron-photon ($e^-e^+\gamma$) plasma generated from vacuum in a focal spot of counterpropagating laser pulses. We rely on a model of purely time-dependent external electric field, but properly take into account quantum radiation from plasma, as well as the semiclassical internal (plasma) field. To achieve this goal we derive a system of coupled kinetic equations for the electron, positron, and photon plasma species supplemented with Maxwell equation for the internal electric field. Quantum radiation is included systematically by taking into account the pair creation/annihilation and radiation channels of the BBGKY chain in quasiparticle representation, which we truncate at second order of perturbation theory. An important application of our results would be consistent consideration of photon emission and cascade production beyond the locally constant field approximation, including the depletion of the driving laser field and a possible scenario of cascade saturation due to thermalization.