Laser pulse-length effects in trident pair production

Laser pulses facilitate multiphoton contributions to the trident pair production e_L^- \to e_L^- + e_L^- + e_L^+, where the label Lindicates a laser field dressed electron (e^- or positron (e^+. We isolate the impact of the pulse envelope in the trident S matrix element, formulated within the Furry picture, in leading order of a series expansion in the classical non-linearity parameter a_0 Generally, the Fourier transform of the...