Radiative double electron capture by bare nucleus with emission of one   photon
  Calculation of the cross-section for the process of double electron capture by bare nucleus with emission of a single photon is presented. The double electron capture is evaluated within the framework of Quantum Electrodynamics (QED). Line-Profile Approach (LPA) is employed. Since the radiative double electron capture is governed by the electron correlation, corrections to the interelectron interaction were calculated with high accuracy, partly to all orders of the perturbation theory. 
E. A. Chernovskaya, O. Yu. Andreev, L. N. Labzowsky
physics.atom-ph