Ne i-like resonance lines and Na i-like satellites in argon and chlorine

Using the beam-foil technique, we have measured the decay times of the resonance lines 2p⁶¹S-2p⁵3s1,3P of Ne i-like Cl viii and Arix. We compare our results with theoretical values of the absorption oscillator strengths of these transitions and those of lighter ions of the isoelectronic sequence. We have partially resolved the Na i-like satellite spectra and suggest some identifications based on relativistic Hartree-Fock calculations. Some new observations of transitions between $n=3$ and $n=4$ levels of the Ne i-like ions are reported.