title: Effective mass signatures in multiphoton pair production.
abstract: Electron-positron pair production in oscillating electric fields is investigated in the nonperturbative threshold regime. Accurate numerical solutions of quantum kinetic theory for corresponding observables are presented and analyzed in terms of a proposed model for an effective mass of electrons and positrons acquired within the given strong electric field. Although this effective mass cannot provide an exact description of the collective interaction of a charged particle with the strong field, physical observables are identified which carry direct and sensitive signatures of the effective mass.
authors.affiliation: Institut für Physik, Karl-Franzens-Universität, A-8010 Graz, Austria and Theoretisch-Physikalisches Institut, Abbe Center of Photonics, Friedrich-Schiller-Universität Jena, D-07743 Jena, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Kohlfürst
authors.affiliation: Theoretisch-Physikalisches Institut, Abbe Center of Photonics, Friedrich-Schiller-Universität Jena, D-07743 Jena, Germany and Helmholtz-Institut Jena, Fröbelstieg 3, D-07743 Jena, Germany.
authors.forename: Holger
authors.initials: H
authors.lastname: Gies
authors.affiliation: Institut für Physik, Karl-Franzens-Universität, A-8010 Graz, Austria.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Alkofer