SEMI-EMPIRICAL CALCULATION FOR IONIZATION OF HELIUM BY ELECTRON IMPACT Alexandre Pereira Chahad+, Ronaldo Santos Barbieri* + Departamento de F=EDsica , * Departamento de Quimica Universidade Federal de Sao Carlos The Binary-Encounter-Bethe(BEB) model, as proposed by Kim and Rudd in 1994, was extended by Coimbra and Barbieri, in 1997, to obtain doubly differential cross section (DDCS)_ for the scattering of electrons by atoms and molecules. In this work, the extended model is employed for He.