Energy levels and spectral lines of Ne VIII

All experimental data on the valence-shell-excited and core-excited spectra of Li-like neon, including previously unpublished beam-foil spectroscopy data, have been compiled and critically evaluated. Seventeen spectral lines have been newly identified. Sets of recommended energy levels have been derived from the total list of observed lines and from selected results of theoretical and semi-empirical calculations. An accurate value of the ionization potential has been derived from existing theoretical calculations

Energy levels and spectral lines of Ne VII

All experimental data on Ne VII, including previously unpublished beam-foil spectroscopy data, have been compiled and critically evaluated. More than a hundred spectral lines have been newly identified. For 40 transitions, the previous identifications have been revised. These revisions resolved all existing contradictions between previously published interpretations of the spectrum. An optimized level scheme has been derived from the total list of observed lines. About a hundred new energy levels have been found, including several highly excited hydrogenic levels. Based on these newly determined levels, as well as on the analysis of theoretical data, the ionization potential has been newly determined with improved confidence

Classifications of some transitions in doubly excited Li i and Li II

Using the beam-foil technique, we have observed several new transitions in lithium between 100 and 2000. We suggest classifications for some of these transitions in the doubly excited term schemes of Li I and Li II. The lifetimes and wavelengths of the Li II transitions are found to be in reasonable agreement with variational calculations. © 1973 The American Physical Society

High electron stabilization rate in slow collisions of bare Ne

We report cross-section measurements of collisions between bare Ne10+ ions and C60 at two different collision velocities (v=0.3 and 0.64 a.u.). We focus our attention on small impact parameter collisions ($b<{\rm C}_{60}$ radius), in which C60 can be considered as a nanometric solid target. The final charge state distribution corresponding to these small impact parameter events is modeled using a multi-cascade charge equilibration model. We show that for bare Ne10+ ions, the initial emptiness of the n=1 shell leads to higher rates for the stabilization on the projectile of the first two electrons

High formation yields of negative ions in multicharged fluorine

We have measured the yield of negative fluorine ions in F$^{q+}$(q=1\tx{--}3)-C60 collisions at low velocity (v \approx 0.18\un{a.u.}). These yields are found surprisingly high, up to 7.1% for F+ and 1.1% for F3+, much higher than the yields measured with atomic targets, typically 0.1%. From the measured kinetic energy loss of scattered F- ions we have estimated the impact parameter of the collision. A direct population of the ground state of the negatively charged projectile by a collective electron transfer is proposed as a possible mechanism to account for the high negative ion formation yields

Emission of singly and doubly charged light fragments from C 60 r + ( r = 4 – 9 ) in Xe 2 5 + − C 60 collisions

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