Multiple ionization produced in Yb due to N-, Si- and Ti-ion impact

Heavy ion induced inner shell ionization produces multiple vacancies in the outer shells (M, N etc.) simultaneous to vacancies in the inner-shells (vi z. L-shell), which in turn create a very complicated electronic configurati on. Three projectiles N-(2+,3+), Si-(7+,8+) and Ti-(10+,11+) ion beams havi ng a range of 0.3 to 3.5 MeV/u were bombarded on a thin rare earth target o f Yb. The recorded L X-ray spectra of Yb have been analyzed in the light of multiple ionization produced due to the heavy ion impact. The outer-shell vacancies acting as spectator vacancies cause a shift in the energy of the various emitted L X-ray diagram lines. A comparison of the shifts in the en ergies of the various L X-ray transitions of Yb due to the impact of these projectiles, from standard values and that due to proton impact along with the deviation of the intensity ratios from single hole branching ratios, re veal a dependence of multiple ionization on the projectile atomic number (Z ) and energy. A further comparison of the degree of multiple ionization pro duced in Yb, evident by the number of spectator vacancies produced due to t he impact of projectiles with 7 less than or equal to Z less than or equal to 22 and overlapping MeV/u range lead to explicit conclusions regarding th e probability of multiple vacancy production in outer shells simultaneous t o a single L-shell vacancy for such projectile target combinations.