L X-ray emission from high-Z elements after ionisation by 1 MeV u^-1Ag ions

Ta, Au and Th L X-ray energy shifts induced by 0.6, 1.2, 2.4 and 4 MeV/nucleon Kr ions

“…Solving these equations for n M and n N leads to the results given in [29], who for a 1 MeV/n Ag beam incident on Au reported very high numbers of spectator vacancies in the M, N and O shells: n M = 7, n N = 20 and n O = 7. This discrepancy most probably results from their underestimation of the energy shift of the Lα line resulting from an N vacancy (0.5 eV), which is approximately a factor of ten smaller than the commonly adopted values (about 6 eV).…”

“…The effect of O and outer more electron vacancies is generally neglected because, as suggested by Parente et al [28] and Uchai et al [29] the number of O vacancies still present at the moment of the radiative transition is probably lower than the one of N vacancies. We observe that on this model, the shifts per M vacancy of Lα 1 and Lβ 1 lines are equal just as the ones of the Lβ 2 and Lγ 1 lines.…”

L-shell ionization in Au by O5+-and Ni5+-ion impact

“…The presence of spectator vacancies in the M and other higher shells increases the binding energy of the atomic levels because of the less screening of the nuclear charge [10]. The increase in the binding energy of the inner shells is more as compared to the outer shells, thus increasing the binding energy difference between any two levels, causing the increase in energy of the emitted X-rays.…”

“…The number of vacancies in the N-shell have been calculated using the scaling procedure illustrated by Uchai et at. [10]. According to this, the observed intensity ratios are compared to the Scofield rates corrected for multiple ionization by multiplying it with an appropriate statistical scaling tactor …”

“…They also observed an energy shift of 30 eV in the Le line at 5 MeV/amu for Oxygen beam on Au, thereby indicating the existence of only one spectator vacancy in the M-shell. Uchai et al [10] have concluded the existence of 7, 20 and 7 spectator vacancies in the M-, N-and O-shells respectively, by 1 MeV/amu Ag-ion impact on Au. The multiple ionization in Au has also been studied by Berinde et al [11] for C, F, Mg, Si, S & Cu projectiles in the energy range 0.5 to 2.5 MeV/amu.…”