Photon angular distribution of radiative electron capture into high-Z projectiles: A brief review

Abstract

With the revolutionary development in the design of heavy-ion cooler storage rings and detectors, increasing interest is being focused on ion-atom collisions, in which the projectiles with a velocity comparable to the speed of light and the electronic transitions in inner shells of high-[Formula: see text] ions are involved. For this purpose, a fundamental interaction mechanism between a photon and an atomic electron in the presence of a strong Coulomb field is reviewed from the perspective of radiative electron capture into highly-charged ions. This is followed by the discussions of photon-electron interactions beyond the dipole approximation, which can be unambiguously visible in the photon angular distributions. In addition, the interference between the leading electric dipole transition [Formula: see text] and the magnetic multipole transition [Formula: see text] for the case of Lyman-[Formula: see text] radiation in hydrogen-like projectiles is also discussed.