K-shell photoionization of ground-state Li-like carbon ions [C3+]: experiment, theory and comparison with time-reversed photorecombination

Absolute cross sections for the K-shell photoionization of ground-state Li-like carbon [C3+(1s22s 2S)] ions were measured by employing the ion–photon merged-beams technique at the Advanced Light Source. The energy ranges 299.8–300.15 eV, 303.29–303.58 eV and 335.61–337.57 eV of the [1s(2s2p)3P]2P, [1s(2s2p)1P]2P and [(1s2s)3S 3p]2P resonances, respectively, were investigated using resolving powers of up to 6000. The autoionization linewidth of the [1s(2s2p)1P]2P resonance was measured to be 27 ± 5 meV and compares favourably with a theoretical result of 26 meV obtained from the intermediate coupling R-matrix method. The present photoionization cross section results are compared with the outcome from photorecombination measurements by employing the principle of detailed balance.