REFRACTIVE ALPHA-NUCLEUS SCATTERING - A PROBE FOR THE INCOMPRESSIBILITY OF COLD NUCLEAR-MATTER

Refractive alpha-nucleus scattering observed at intermediate energies is of great help in determining the alpha-nucleus potential at small d istances, where the overlap density is large. A systematic folding ana lysis of the elastic alpha + C-12, Ca-40 and Zr-90 scattering data at E(lab) = 59.1 - 172.5 MeV has been performed using effective density d ependent NN interactions based on the G-matrix elements of the Reid- a nd Paris NN potentials. The new interactions consistently reproduce th e saturation properties of cold nuclear matter and generate, at the sa me time, different values of the nuclear incompressibility K. With the existing refractive scattering patterns, it is possible to conclude f rom our folding analysis that a nuclear incompressibility K similar or equal to 220 +/- 50 MeV is the most realistic one.