Multiple ionization in 67Ho and 71Lu due to the impact of nitrogen- and silver-ions

The energies of various L X-ray transitions namely Ll, Lα, Lη, Lβ1,4, Lβ3,6, Lβ2,15, Lβ5,7, Lβ9,10, Lγ5, Lγ1, Lγ2,3 and Lγ4 have been measured in 67Ho and 71Lu due to the impact of 5-11 MeV N3+,4+ - and 90-180 MeV Ag7+, 8+, 12+,14+- ions. The change in the energy values of various transitions from the standard values have been calculated from the changes in the positions of the centroids of various L X-ray peaks after fitting the L X-ray spectra of these elements using NFIT computer program. Since the energy shifts are caused due to the multiple ionization of the M-, N-, O- shells simultaneous to the L-shell ionization, the measured energy shift values have been compared to the corresponding single-hole values to calculate the number of spectator vacancies caused in the outer-shells simultaneous to inner-shell ionization. Only one M-spectator vacancy is estimated in both 67Ho and 71Lu elements due to N-ion impact while 5 −7 M spectator vacancies in 67Ho and 6-8 M spectator vacancies in 71Lu are estimated for Ag-ion impact. It is evident from the measured intensity ratios (higher than the single-hole values) for the transitions Lβ1(L2-M4)/Lγ1(L2-N4) and Lα(L3-M4,5)/Lβ2,15 (L3-N4,5) and lower than the single hole values for Lγ2,3(L1-N2,3)/Lγ4(L1-O2,3) that more vacancies are caused in the N-shell than in the M-shell and a lower degree of multiple ionization in the O-shell than in the N-shell. The number of spectator vacancies caused by Ag-ion impact has been found to be 5-7 for M- and 19-22 for N-shell in 67Ho and 6-8 M-shell and 12-22 for N-shell in 71Lu respectively.