22nd SPARC Topical Workshop

Compton scattering is one of the fundamental processes in light–matter interaction in which an incoming photon is inelastically scattered off an electron. In the energy range from a few keV to several MeV, Compton scattering makes a significant contribution to the light-atom coupling. It therefore has a wide range of important applications across various fields of modern science, from radiotherapy in medicine to X-ray polarimetry. The latter is of particular interest to the SPARC collaboration, where the development of Compton polarimeters is a key objective. In this context, we present theoretical studies of Compton scattering from bound electrons, with special emphasis on polarization effects. In particular, we discuss calculations within the framework of S-matrix theory and independent particle approximation (IPA). To perform these calculations, a program was developed to numerically solve the radial Dirac equation efficiently and accurately for a bound electron in the central potential of its nucleus, which is approximated by a Coulomb potential. Based on this, detailed calculations of the doubly differential cross section (DDCS) and the polarization behavior of the outgoing photon can be carried out across a wide range of energies and for arbitrary polarization states of the incoming photon beam.