Projectile Charge State Dependence of M-Shell Ionization of Au, Pb, Bi and U by 1.42-MeV/amu Fluorine Ions

The present study was undertaken to determine the direct ionization and electron capture contributions to vacancy production in the M-shells of 79Au, 82Pb, 83Bi and 92U for incident 199F ions. M-shell x-ray production cross sections have been measured for 1.42-MeV/amu 199Fq+ ions for q=4,5,6,8,9. Enhancements in the target x-ray production cross sections were observed for projectiles with one and two K-shell vacancies over those without K-shell vacancies. Direct ionization and electron capture contributions to the vacancy production were extracted from the data and compared to the plane wave Born approximation and to the Oppenheimer-Brinkman-Kramers calculations of Nikolaev, respectively.