MEASUREMENTS OF IONIZATION CROSS-SECTIONS OF 4D-ELECTRONS IN XENON BY ELECTRON-IMPACT

Partial ionization cross sections for 4d-electrons in xenon by electron impact have been measured by means of a combination of the electron-energy-loss spectroscopy and the Auger electron spectroscopy in the impact energy region from 70 eV to 4 keV. The cross sections increase with the impact energy rapidly from the threshold and display a sharp maximum, whose value is (17.0+/-3.5) x 10(-18) cm2, around 120 eV impact energy, revealing an existence of a resonance. The cross sections arise again from a minimu m at about 200 eV and exhibit a broad maximum of (14.5+/-3.0) x 10(-18) cm2 around 500 eV. Absolute scale of the cross section is determined using the generalized oscillator strengths for the 4d-ionization, which are measured by the electron-energy-loss spectroscopy. Relative cross sections are measured as a function of the impact energy using an Auger line assigned to the N5O2,3O2,3 (S-1(0)) fine. Experimental results are compared with a previous experimental result given by a different procedure and a result of a theoretical calculation.