Second Born approximation to the Bremsstrahlung differential cross-section

Abstract

In this paper we calculate the second Born approximation contribution to the Bremsstrahlung cross-section differential in both the photon and electron angles. This is divergent if a Coulomb potential is considered, but it is found, on following the idea of Dalitz (1951), that all observable quantities turn out to be finite when we perform the calculation for a Yukawa potential and take the limit of zero screening. It is shown that this is true to order Z$^{3}$ in the differential cross-section before it is averaged over spins, and the cross-section is calculated explicitly for the case of an unpolarized beam when the final states of polarization are not observed. Further, it is pointed out that the same methods can be applied satisfactorily in the case of pair production.