PERIPHERAL N ALPHA-SCATTERING - A TOOL FOR IDENTIFYING THE 2 PION EXCHANGE COMPONENT OF THE NN POTENTIAL

We study elastic N alpha scattering and produce a quantitative correla tion between the range of the effective potential and the energy of th e system. This allows the identification of the waves and energies for which the scattering may be said to be peripheral. We then show that the corresponding phase shifts are sensitive to the tail of the NN pot ential, which is due to the exchange of two pions. However, the presen t uncertainties in the experimental phase shifts prevent the use of N alpha scattering to discriminate the existing models for the NN intera ction. [S0556-2813(98)04504-X].