Nonadiabatic effects in scattering by deuterons

It is shown under some general assumptions that for small transferred momenta Δ < or approximately 1/R (R is the deuteron radius) significant compensation of the following nonadiabatic effects occurs: effects connected with the nonstatic nature of nucleons (involving recoil in elementary scattering acts) cancel out with the contribution of processes in which rescattering of nucleons by each other occurs when the impinging particle is consecutively scattered by different nucleons; effects connected with variation of amplitude of the elementary process on moving off the energy surface cancel out with the contributions of processes in which a nucleon which successively scatters the impinging particle interacts with the other nucleon of the deuteron. It may occur at high as well as low and intermediate energies and can help to elucidate the causes of the success and the range of applicability of widely used multiple scattering theories based on the concept of fixed (''frozen'') nucleons. The cancellation also shows how dangerous attempts of ''partial'' improvement of simple theories may be