title: Trident pair production in strong laser pulses.
abstract: We calculate the trident pair production amplitude in a strong laser background. We allow for finite pulse durations, while still treating the laser fields nonperturbatively in strong-field QED. Our approach reveals explicitly the individual contributions of the one-step and two-step processes. We also expose the role gauge invariance plays in the amplitudes and discuss the relation between our results and the optical theorem.
authors.affiliation: Department of Physics, Umeå University, SE-901 87 Umeå, Sweden. anton.ilderton@physics.umu.se
authors.forename: Anton
authors.initials: A
authors.lastname: Ilderton