ISOSCALAR TRANSITION RATES FROM INELASTIC ALPHA-SCATTERING

Isoscalar transition probabilities [B (IS-lambda)] have been obtained from the analysis of inelastic a scattering using double-folded optical alpha-nucleus potentials. The reliability of the proposed method was tested by applying it to three nuclei representing limiting cases of nuclear structure models. Data on Pb-208 have been analyzed at E(alpha) = 23.5, 79.1, 104, and 139 MeV using the hydrodynamical model. For Er-168 (E(alpha) = 36 MeV) the model of the asymmetric rotor and for Pd-108 (E(alpha) = 30.5 MeV) the model of the harmonic vibrator was considered. Excellent agreement of the extracted B (IS-lambda) values with the corresponding B (E-lambda) values (obtained from electromagnetic probes) has been reached. The result of a lifetime measurement for the two-quadrupole-phonon 4+ state at 2055 keV in Er-168 has been confirmed.