Electron Self-Energy in Intense Plane-Wave Field

Publisher Website
Google Scholar
Abstract
The self-energy for an electron in an intense external plane-wave field is calculated in perturbation theory. It is demonstrated that the Feynman-Dyson perturbation series may be summed exactly and in closed form with the neglect of the small self-field effects. In order to facilitate the summation, an earlier method is modified to accommodate off-mass-shell momenta for the electron. The momentum-conserving part of the full Green's function is then defined and computed. By adopting Volkov boundary conditions, which specify the plane-wave field to be monochromatic, we obtain a mass shift which agrees with the shift discussed by Sengupta and others. The mass shift is discussed briefly in connection with the question of a frequency shift in strong-field Compton scattering; and the momentum dependence leads to some remarks on the relation between the present calculation and its analog in ordinary quantum electrodynamics.