Delbr\"uck scattering above the pair production threshold: Going beyond the Born approximation
Abstract
We present a theoretical method to calculate Delbr\"uck scattering amplitudes for photon energies above the electron-positron pair production threshold. The method is based on the application of the relativistic Dirac-Coulomb Green function and describes the interaction of the virtual pair with the Coulomb field of a target to all orders in the coupling strength parameter . To illustrate the application of the developed approach, detailed calculations have been performed for the scattering of 2.754~MeV photons off bare ions with a wide range of nuclear charge numbers. Results of these calculations clearly indicate that the higher-order terms beyond the Born approximation lead to a strong enhancement of the imaginary part of the Delbr\"uck amplitude and have to be taken into account for the analysis and guidance of gamma-ray scattering experiments.
Keywords
Cite
@article{arxiv.2308.01610,
title = {Delbr\"uck scattering above the pair production threshold: Going beyond the Born approximation},
author = {J. Sommerfeldt and V. A. Yerokhin and A. Surzhykov},
journal= {arXiv preprint arXiv:2308.01610},
year = {2023}
}