The Generation of High-Energy Electron–Positron Pairs during the Breit–Wheeler Resonant Process in a Strong Field of an X-ray Electromagnetic Wave

Abstract

The Breit–Wheeler resonant process was theoretically studied in a strong X-ray electromagnetic wave field under conditions when the energy of one of the initial high-energy gamma quanta passes into the energy of a positron or electron. These conditions were realized when the energy of a high-energy gamma quantum significantly exceeded the characteristic Breit–Wheeler energy, which was determined using the parameters of the electromagnetic wave and the initial setup. Analytical formulas for the resonant differential cross-section were obtained. It is shown that the resonant differential cross-section significantly depends on the ratio between the energies of the initial gamma quanta and the characteristic Breit–Wheeler energy. With a decrease in the characteristic Breit–Wheeler energy, the resonant cross-section increases sharply and may exceed the corresponding non-resonant cross-section by several orders of magnitude. The results make it possible to obtain narrow beams of ultrarelativistic positrons (electrons) with energies of the order ∼102 GeV and could also be used to explain high-energy fluxes of positrons (electrons) near neutron stars, as well as to simulate QED processes in laser fusion.