Calculation of the cross section of radiative double-electron capture by a bare nucleus with emission of one photon

We present a calculation of the cross section for the process of double-electron capture by a bare nucleus with emission of a single photon. The calculation is performed within the framework of quantum electrodynamics. The cross section is presented as a function of the incident-electron energy for ions with the nuclear charge within the interval $8\ensuremath{\le}Z\ensuremath{\le}92$. The available experiments on the double-electron capture by a bare nucleus are discussed.