Differential rates for multiphoton pair production by an ultrarelativistic nucleus colliding with an intense laser beam

We study nonlinear electron-positron pair creation in the process where huge amounts of energy and momentum are imparted into the physical vacuum due to the collision of an ultrarelativistic nucleus with a high-intensity laser beam. We use an approach which fully accounts for the interaction of the leptons with the laser field, while the treatment of their interaction with the nucleus is restricted to the first order of perturbation theory. We calculate energy and angular spectra for one of the produced leptons, and the total production rate as a function of the energy of the nucleus. Our results suggest that by the aid of the upcoming accelerator generation, pair production in such collisions might be experimentally observable. Moreover, according to our calculations, the pair creation occurs as a highly nonlinear process far above the energy threshold, which leads to distinct features of the differential production rates.