Double Excitation of Helium by Electronic Impact

Abstract

The cross section for electron impact excitation of He to the doubly excited (2p)/sup 2/ /sup 3/P/sub 3/ state was calculated. This state is the lowest lying, doubly excited state that is stable to autoionization. The differential cross sectlon results indicate that the scattered beam has an intensity maximunm at right angles to the incident beam. The total cross section shows the fairly sharp peak and rapid decay with increased electron energy characteristic of exchange reactions. The transition cross section is compared with others. (D.C.W.)