Charge Transfer Cross Sections for Uranium

Abstract

Symmetric charge transfer cross sections between singly ionized ions and their parent atoms were measured for uranium in the impact energy range of 100–1200 eV. A primary ion beam was extracted from a laser ion source in which the atoms were ionized by laser resonant photoionization. The slow ions produced in the charge transfer reaction and the fast primary ions were detected with Faraday cups. The cross sections were determined from the ratio between the number of ions produced in the charge transfer reaction and that of the primary ion beam. The cross sections increased with ion impact energy from (1.3±0.3)×10-14 cm2 at 100 eV to (2.7±0.3)×10-14 cm2 at 1200 eV. The increase in the cross sections above 100 eV was well reproduced by theoretical calculations that took into consideration the electronic configurations of uranium atoms and ions.