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Data on continuum electron capture and loss for bare and highly ionized C a+ ,O a+ ions traversing Ar at energies 1.6-2 C 8 MeV/A reveal striking disagreements with corresponding theories. We demonstrate a velocity-independent (~z 2 ' 2±0t2 ) scaling for continuum capture by bare ions, a Z -independent velocity scaling, and an approximately ^-independent (q = 6,7,8) equality of continuum electron-capture and -loss cross sections at velocities corresponding to ~ 2 MeV/A 0

The lifefimes of the (2p)2 P 3/2 level in Si XII and the (2p 2)3 P 2,1,0, (2s2p)1 P 1 and the (2p 2)1 D 2 levels in Si XI have been determined using the beam-foil method. It is proposed that existing discrepancies between experimental and theoretical f values for the (2s 2)1 S 0-(2s2p)1 P 1 transition in some ions of the Be sequence may be the result of the inability of the experimentalist to account for strong cascading from the (2p 2)1 S 0 level.

The foil-excitation method has been used to study the extreme ultraviolet spectra of highly ionized oxygen and fluorine. Several previously unreported lines in heliumlike fluorine are reported and other newly reported lines in heliumlike oxygen have been measured to higher accuracy. Included in the measurements are certain heliumlike oxygen transitions of significance in interpretation of solar-flare spectral observations. The wavelength determinations are usually in good agreement with calculated results which includes relativistic corrections but discrepancies arise when nonrelativistic calculations are used. A comparison of the present results and those recently obtained by 8-pinch and laser-induced plasma sources is made for both heliumlike and lithiumlike ions; a few discrepancies occur, with our results in most cases in better agreement with relativisitically corrected calculations. Certain unidentified lines in the spectra may be attributable to radiative transitions between quartet states of lithiumlike ions.

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