Photon angular distributions from radiative electron capture in relativistic atomic collisions

A detailed discussion is given of the general behavior of differential cross sections for radiative electron capture in relativistic and nonrelativistic heavy-ion--atom collisions. From angular-momentum conservation and a simple approximate treatment, the basic qualitative features can be derived in an analytic form. Subsequently, the results of rigorous relativistic calculations are presented graphically for a sequence of projectile charges and projectile energies. It is shown that in radiative electron capture, the influence of the electron spin manifests itself in a particularly clear-cut way