Few-Photon Electron-Positron Pair Creation by Relativistic Muon Impact on Intense Laser Beams

Electron-positron pair production in combined laser and Coulomb fields is studied. To this end, the Feynman diagram for multiphoton pair creation by muon impact on a circularly polarized high-frequency laser beam is evaluated within the framework of laser-dressed quantum electrodynamics employing relativistic Volkov states. In the limit of low laser intensity, the result is shown to coincide with the known expression for multiphoton pair creation by a proton which is treated as an external Coulomb field. A scaling of the total pair creation rate is analyzed. The recoil distribution is calculated numerically and its dependence on the projectile mass is discussed. Energy spectra of the created particles and angular spectra of the scattered muon are presented.