Giant resonances in Mg-24

Abstract

The giant resonance region in Mg-24 was studied with inelastic scattering of 240 MeV alpha particles at small angles including 0 degrees. The giant resonance peak was found to extend up to E-X = 41 MeV. Isoscalar E0, E1, and E2 strength corresponding to 72+/-10%, 81(-14)(+26)%, and 72+/-10% of the respective energy weighted sum rules was identified in the peak with centroids of 21.0+/-0.6, 18.8+/-1.7, and 16.9+/-0.6 MeV and rms widths of 7.3 +/-1.2, 6.7+/-1.0, and 3.4+/-0.5 MeV, respectively. Elastic scattering was measured from theta(c.m.) = 3 degrees to 33 degrees and density dependent folding model parameters obtained. Inelastic scattering to states at 1.369, 4.122, 4.238, 6.010, 6.432, 7.349, 7.555, 7.616, and 8.358 MeV was measured and B(EL) values obtained.