The statistical multistep compound (SMC) theory of Feshbach, Kerman and Koonin (FKK) is used to analyse the energy and angular distributions of 14 MeV neutrons inelastically scattered by 59C0 and 93Nb. An acceptable fit is obtained to the whole energy spectrum provided the contributions from the (n, 2n) and (n, pn) reactions, also calculated with the SMC formalism, are added at low energies. The theory also accounts well for the (n, p) cross sections. The sensitivity of the results to the level density parameters is investigated.

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A new approach to calculate the exact eikonal (unrestricted Glauber) direct and exchange amplitudes is proposed and applied, as a test case, to the elastic scattering of electrons and positrons by atomic hydrogen. The six-dimensional integrals of the eikonal direct and exact exchange amplitudes have been reduced to simple one-dimensional integrals, in contrast to the double integrals obtained so far. These one-dimensional integrals have been evaluated numerically using a quadrature method. Both the post and the prior forms of the exchange integrals have been computed and no post-prior discrepancy is noted for elastic scattering. Numerical results have been compared with some existing theoretical results and experimental findings.

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