Lifetime measurements obtained by the beam-foil method are given for 13 levels in In II and 12 levels in In III. Particular attention has been paid to cascade correction with the application of a new arbitrarily normalized decay curves (ANDC) program. The results are compared with theory, and good agreement is found with recent multiconfiguration relativistic Hartree–Fock (MCRHF) calculations for the In II resonance transition. The results for 2P and 2D levels in In III and 1D levels in In II indicate a need for further calculations.

Assignments are suggested for 32 transitions in Ar VI involving doublet levels in the 3p' and 3s3p3d configurations. Beam-foil decay curves are used to measure the lifetimes of these levels, the results being systematically about 25% longer than the values calculated by Fawcett. These decays are also used in ANDC analyses of the lifetimes of the 3.13~' 2S, *P, 2D and 3?3d 'D levels, where the agreement with Fawcett's calculation is generally good. A discussion is also given of the alternative analysis of the Ar VI spectrum recently published by Lesteven-Vake et al. using recoil-ion techniques.a Configuration-interaction calculation using scaled Slater integrals [6].Analysis incorporating cascade data from 3s3p('P)3d 'P.Analysis incorporating cascade data from 3s3p('P)3d ' P , 3s3p('P)3d 2P and '0.Analysis incorporating cascade data from 3p' ' P and '0.e Analysis incorporating cascade data from 3s3d('P)3d 'F, 3s3p('P)3d 2D and 'F.

Some practical methods are suggested for applying the Arbitrarily Normalized Decay Curve (ANDC) method for cascade-correction in beam-foil lifetime measurements. These methods are used to analyze decay curves recorded for the ns2S-np2P0 resonance doublet in Ar VIII, Kr VIII and Xe VIII by including the np2P0-nd2D cascade transitions in the analysis. The f-values derived from the np lifetimes for the ns-sp multiplet are in good agreement with recent theoretical estimates for Ar VIII and Kr VIII and agree with theory for Xe VIII within the combined experimental and theoretical uncertainties.

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High-resolution ionization efficiency curves using electron impact (58 -59 eV) on helium are presented. Two previously unknown structures are clearly seen in the spectra at 58.415+0.005 and 58.48+0.02 eV in addition to the large (He*) 2s2p ( D) negative-ion resonance. The line-shape parameters for the 'D state obtained by fitting the data to theoretical line profiles are E"=58. 283+0.003 eV, I'=59%4 meV, and Q = -0.70+0.04. The two new structures are tentatively assigned to the (He ) 2p' electron configuration.