Electron–positron pair production by linearly polarized photon in the nuclear field

Process of lepton pair production by polarized photon on nuclei can be used to measure the degree of linear polarization of high energy photon. The differential cross section and the analyzing power are calculated with taking into account higher powers of expansion in Zα. Pure Coulomb and screened potential are considered. The results are illustrated in terms of asymmetry. The screening effect as well as the effect of higher orders expansion in Zα   is shown to vanish in limit of pair emission angles exceeding m/ωm/ω.