A DWBA calculation of electron pair production including exponential screening in the intermediate energy range (1-5 MeV)

Calculation of electron screening corrections to pair production at intermediate energies have previously made use of the approximation that screening effects and coulomb distortion are independent of one another at high energies. The accuracy of this approximation is suspect at lower energies where coulomb distortion effects are large. A DWBA calculation of pair production that uses an exponentially decaying Coulomb potential as a model of electron screening will be presented in this paper. The Dirac equation is solved for this potential and the property normalized Dirac-Screened scattering wavefunctions are constructed. Differential and total cross sections are calculated for this screened potential in the energy range of 1-5 MeV and are compared with the unscreened DWBA cross sections