Angular distributions of charge exchange collisions at very low energies

Abstract We have measured angular distributions of double-electron capture in C 4+ →He collisions at energies between 400 and 800 eV. The experimental energy-gain spectra show that the ground state of C 2+ (1s 2 2s 2 ) is populated. In the angular distributions we observe an interference pattern which is attributed to Stueckelberg oscillations. The presented results are compared to experimental data as well as to theoretical calculations by other authors.