[en] It was shown that inclusion of capture to higher n shells of the projectile provides significantly improved agreement with experiment. The basic idea is that practically all capture into higher-lying (n > 2) quartet states decay radiatively very quickly to the 1s2s2p ⁴P state. These photon cascades become increasingly more likely than autoionization with increasing n. Due to the strongly different decay rates, the metastable 1s2s2p ⁴P state behaves like a quasi-ground state, collecting all quartet capture events before decaying itself. (R.P.)