INDIRECT X-RAY-LINE FORMATION PROCESSES IN HIGHLY CHARGED BARIUM

We have studied indirect excitation processes contributing to the x-ray line emission of neonlike barium (Ba46+) interacting with an electron beam. Techniques are presented which resolve the contributions due to electron capture by fluorinelike ions and inner-shell ionization of sodiumlike ions from contributions due to direct electron-impact excitation and radiative cascades. The strength of resonance excitation of the 2pε3s magnetic quadrupole line through intermediate levels 4lnlε (n=5,6) is measured to equal S=(2.8±0.8)×10-19 cm2 eV. © 1990 The American Physical Society.