Speaker
Description
We study electron-positron pair creation induced by the field of two colliding (transversal and linearly polarized) laser pulses ranging from the Sauter-Schwinger regime at small laser frequencies to the Breit-Wheeler regime at large photon energies.
On the basis of a generalized WKB approach, we find that the pair creation rate along the symmetry axis (where one would expect the maximum contribution) displays the same exponential dependence as for a purely time-dependent electric field. The pre-factor in front of this exponential contains the corrections due to focusing or de-focusing effects induced by the spatially inhomogeneous magnetic field. Through this new method, we can thus not only reproduce particle production rates within a purely time-dependent toy model approach but also analyze the distortions the magnetic field creates with respect to the particle momentum spectrum as well as the total yield.
