Abstract
Wallace's (WSOEA) second-order eikonal approximation is used to calculate elastic differential cross sections for e-or+-H and e-or+-Ar scattering at 100 and 500 eV in the angular range 0-20 degrees . The predictions of the WSOEA are compared with those of the partial-wave calculation (PWC), in addition to the results obtained in the first Born approximation (FBA) and Glauber's first-order eikonal approximation (FOEA). The WOSEA shows a definite improvement upon the FBA and the FOEA and yields cross sections in good agreement with the PWC results.