Uranium atoms and ions in the gas phase. Progress report, March 1, 1977--February 28, 1978

Abstract

Work directed toward understanding associative ionization reactions of uranium atoms in the gas phase with gases, and subsequent reactions of ions formed by associative ionization reactions with other gases is reported. Processes are being investigated which either might be used in the separation of uranium isotopes (and other isotopes which can engage in associative ionization) or which affect other isotope separation methods (such as laser isotope separation methods). Research is reported devoted to electron spectroscopy of electrons produced in associative ionization reactions; measurement of the absolute collision cross sections, where associative ionization is used to monitor the absolute number density in a U atom beam, and study of ion-molecule reactions or uranium oxide ions. Studies of electron energy distribution show that electrons in the U + O/sub 2/ reaction are produced with very low energies, implying that the UO/sub 2//sup +/ ions are formed in very highly excited states. Collision cross section measurements indicate that the cross section for producing U/sup +/ is somewhat smaller than anticipated having a peak cross section of about 6.5 x 10/sup -16/ cm/sup 2/ at an electron energy of about 30 eV. Double cross beam experiments are in progress to clarify results of UO/submore » 2//sup +/ + NO/sub 2/ ion-molecule reactions. (JRD)« less