LOW-ENERGY INTERACTION OF ETA-MESONS WITH LIGHT-NUCLEI

Near-threshold scattering of eta-meson from light nuclei H-2, H-3, He- 3, and He-4 is considered on the basis of approximate few-body equatio ns. The position and movement of poles of the elastic scattering ampli tude have been studied. It was found that, within the existing uncerta inties for the elementary eta N interaction, all these nuclei can supp ort an eta-nucleus quasi-bound state. A steep increase of the eta(4)He phase-shift by pi is found at a c.m. energy of similar to 10 MeV, whi ch indicates that a near threshold resonance exists in this system.