Abstract
(CSDA) ranges for electrons in the elements Calcium , Potassium and Phosphor in terms of energy (0.01 - 10) MeV have been studied by using two empirical formula of Berger-Seltzer and Tabata et al respectively . These two parameters depend upon the atomic number (Z) of the absorber and incident electron energy E. It has been found that these formulae gives better agreement with the available data of Estar universal code. In this paper ,we present the results of Radiative Energy Loss and continuous slowing down approximation