C.F. Moore

Projectile and target dependence of the K

Proton, alpha -particle. and oxygen-ion beams are used to induce K alpha x-ray spectra in the elements Ca. Sc. Ti, V, Cr. and Mn. The target dependence of the satellite structure for Z = 20 to Z = 25 is studied. The relative intensity ratios for the production of one K-shell and multiple L-shell vacancies are measured. These ratios are compared with the predictions of the binary-encounter approximation (BEA) and the semiclassical approximation (SCA) for multiple ionization. The data strongly reflect the statistical approach used in the theories. The BEA theory agrees well with the proton and alpha -particle data but does not give good agreement with the oxygen data. (auth)

alpha

Abstract Presented here are the energies of all of the possible Auger-electron and X-ray transitions from particular states (described by LS coupling) in Ne 1+ to Ne 7+ and Ne 8+ . The values, calculated with Hartree-Fock wavefunctions, are compared with recent measured values for highly ionized neon produced by energetic heavy-ion bombardment. Comparison is also made with conventional electron bombardment data.

satellite structure

Abstract Measurements of Kα and Kβ X-rays induced by proton, alpha and oxygen particle beams from an electrostatic accelerator show a divergence from the normal X-ray spectrum as the nuclear charge of the incident beam increases. The results of these measurements are consistent with the explanation that the ion excitation produces multiple inner-shell electron vacancies, which in turn causes electronic-shell energy shifts.

Calculated K Auger-electron and K X-ray transition energies for the multiply ionized neon atom☆

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.

A general description of K X-ray de-excitation of titanium☆

Abstract Flourine X-ray spectra produced by proton, alpha particle and oxygen ion bombardment of targets of LiF, NaF, CaF2 have been measured. The Kα satellite yields of fluorine are different in each fluorine crystal due to the electronic structure of the compounds, however, the Kα hypersatellite yields are nearly identical.

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

Abstract High resolution Auger electron measurements of neon have been made using electron, proton, alpha and oxygen ion excitations. Energies and intensities have been extracted for transitions with initial states 3 P and 1 P (with configuration 1s 1 2s 2 2p 5 ). In general, the population ratio of triplet P to singlet P is independent of the type of incident ion, but this ratio is seen to differ significantly from the statistical expectation.

Solid state structure effects in flourine X-ray spectra produced by heavy ion bombardment☆

Abstract Three prominant peaks are observed in Kα X-ray spectra of both Al and Si at energies below the characteristic Kα 1,2 lines. These emission lines were produced by 30 MeV oxygen bombardment and recorded with a crystal spectrometer. The exact origin of these lines is not understood.

Excitation of multiplet states in neon

Abstract For Cl 13+ bombardment the K X-ray transition from the metastable 4 P state in Li-Like Ne is clearly resolved from an overlapping Be-like line. Previously measured K-shell fluorescence yields are corrected for this overlap. The detected rate of metastable to prompt X-ray emission from Li-like Ne is observed to vary with projectile energy.

Anomalous low energy Kα lines in Al and Si from high energy oxygen bombardments

Abstract A high resolution Bragg crystal spectrometer has been used to measure the decay times of the transitions: 1s2 – 1s 2p (1 1S–2 3P) and 1s2–1s 2s 2p (1 2S–2 4P). They are 1.47 ± 0.08 and 3.48 ± 0.08 ns, respectively. Delayed decay has been observed from states with much shorter lifetimes. These result in non-linear curves on a semilogarithmic graph that are all similar to each other. Thus, more than one delayed decay contributes to the formation of these states.

Metastable X-ray emission following violent Cl13+–Ne collisions

X-ray transitions from scandium due to proton, helium, and oxygen bombardment are reported. The oxygen +Sc spectrum displays the largest number of satellites including three hypersatellite transitions and in the He+Sc spectrum double electron transitions were observed. Hartree-Fock-Slater calculated energies were used to assign the transitions.