LOW-ENERGY EXPANSIONS IN NUCLEAR-PHYSICS

The results of recent experimental and theoretical studies of low-ener gy nucleon-nucleon and nucleon-deuteron collisions are studied and com pared with the older data. Special attention is devoted to two problem s: that of the extrapolation of the phase shifts, amplitudes, and cros s sections of such collisions to experimentally inaccessible energies, and that of separating the contributions of nuclear and electromagnet ic interactions in the parameters of low-energy elastic scattering. Va rious classical and recent approaches to the solution of these problem s are analyzed. A method is developed for constructing low-energy expa nsions which permits information on the nuclear interaction to be extr acted from the measured phase shifts in systems of two and three nucle ons or nuclei. The role of electromagnetic corrections to the Coulomb interaction in such scattering reactions can also be studied using thi s method. (C) 1997 American Institute of Physics.