Resonant laser-assisted process of the ultrarelativistic electron-positron pair creation by a gamma quantum in the nucleus field

Abstract

The resonant laser-assisted process of creation of the ultrarelativistic electron-positron pair by a gamma quantum in the nucleus field was studied theoretically. Unlike the processes in absence of laser field, the laser-assisted processes can occur both non-resonant and resonant way. This is explained by the fact that in the field of laser the processes of first order in the fine structure constant are able to take a place. Due to that the process of second order effectively reduces to two successive processes of the first order. The resonant kinematics was studied in details. It was shown that the process has characteristic threshold energy. Resonant differential cross section of studied process was obtained. It’s magnitude significantly exceed the corresponding resonant differential cross section without a laser field. The project calculation can be experimentally verified by the scientific laser plasma facilities of pulsed radiation (SLAC, FAIR, XFEL, ELI, XCELS).