L.E. Smith

Measured K-shell fluorescence yields for multiply-ionized neon☆

Abstract The Ne K-shell fluorescence yields ω i have been measured for single K-shell and i th degree L-shell ionization. For O 5+ bombardment ω i × 100 = 1.8, 1.9, 2.2, 3.1, 5.4, 9.9, and 16.1 for i = 0 to 6, respectively. For the higher charge states ω i is measured to be up to 2 times larger than the theoretical prediction.

Observation of enhanced excitation of 12C by inelastic pion scattering on the (3,3) pion-nucleon resonance

Abstract Pion inelastic scattering on 12 C to states at an excitation energy of approximately 19 MeV shows a strong enhancement at an incident pion energy near the pion-nucleon (3,3) resonance. This resonance may therefore provide a mechanism for the selective enhancement of inelastic transitions.

Observation of a projectile charge dependence for the neon K-auger electron spectrum

Oxygen (plus six) and (plus eight) at 30 MeV incident energy have been used to induce Auger electron spectra of Ne. The high instrumental resolution (0.02% FWHM) spectra show specifically that the charge state of the incident oxygen ion considerably affects the distribution of the K-Auger electron yield among the charge states of multiply ionized neon.

A high resolution study of Ar LMM Auger electrons produced by ion bombardment

Ar LMM Auger electron lines produced by H+, He+, O4+, and O5+ bombardment are measured with high instrumental resolution (0.02% FWHM). Individual heavy ion induced Auger satellite lines are resolved. Two strong lines are observed at 221 and 223 eV in the oxygen induced spectra. The ratio of satellite to normal line production is given for each projectile.

Relative satellite line intensities in Ar K Auger electron spectra produced by 0.4 to 4 MeV proton impact

Abstract A decrease in the intensities in the diagram lines of proton induced Ar K Auger electron spectra with decreasing projectile energies from 4 to 0.4 MeV was measured. The competing increase of the satellite line intensities in the KLL and KLM part of the Ar K Auger spectra was found to be in good agreement with the previously reported projectile energy dependence of satellite line production in Ne K Auger electron spectra.

Auger electron emission spectra from foil and gas excited carbon beams

Auger electron emission spectra from 2 MeV C+ ions excited by collisions with thin carbon foils and Ne gas are presented. The similarity of qualitative features for the C+ → C (foil) and C+ → Ne spectra indicates the similarity of ionization mechanisms for beam foil and beam gas excitation. The spectra were normalized to the lowest lying Li-like quartet state (1s 2s 2p) 4po in carbon by comparison with time delayed foil excited electron decay-in-flight spectra. Comparison to Hartree Fock calculated transition energies indicates that transitions in three and four electron carbon ions dominate the prompt spectra.

High resolution measurements of p+ArKLL and KLM Auger electrons

Initial measurements of ArKLL and KLM Auger electron lines produced by 4 MeV proton bombardment are reported. Energies and relative intensities of all observed peaks are tabulated. For the identifiable KLL transitions, the measured relative intensities are compared to theory.

Energy dependence of π+ induced two- and four-nucleon removal☆

Abstract De-excitation γ-rays have been detected from nuclear states following positive pion induced two-nucleon removal from 12 C and four-nucleon removal from 16 O. Excitation functions for population of discrete states were obtained for positive pions of 75, 125, 150, 200, 225, 250 and 290 MeV. The pion-nucleon (3, 3) resonance is not reflected in the cross sections for either reaction. Implications of the observed energy dependence are discussed.

L X-ray spectra of chlorine in chlorine-neon collisions (and sulphur in argon-H2S collisions)

Chlorine beam L X-rays were detected using a curved crystal spectrometer. Special attention is given to the observed 2p5 to 2p43s multiplet transitions. The L X-ray line intensities for these multiplets in chlorine do not support statistical population of the initial states, in contrast to previously reported chlorine data.

Neon K X-ray spectra excited by O4+ and Cl4+ bombardment

Neon K X-ray spectra resulting from O4+ and Cl4+ bombardment are observed to have dissimilar K alpha satellite intensities. These results are in contrast to similar measurements made using C6+, N6+ and O6+ bombardment.