Deformation effects on isoscalar giant resonances in 24Mg.

Strength distributions for isoscalar giant resonances with multipolarity L=2 have been determined in 24Mg from "instrumental background-free" inelastic scattering of 386-MeV a particles at extreme forward angles, including 0°. The isoscalar E0, E1, and E2 strengths are observed to be 57±7%, 111.1+10.9%-7.2, and 148.6±7.3%, respectively, of their energy-weighted sum rules in the excitation energy range of 6 to 35 MeV. The isoscalar giant monopole (ISGMR) and quadrupole (ISGQR) resonances exhibit a prominent K splitting which is consistent with microscopic theory for a prolate-deformed ground state of 24Mg. For the ISGQR it is due to splitting of the three K components, whereas for the ISGMR it is due to its coupling to the K=0 component of the ISGQR. Deformation effects on the isoscalar giant dipole resonance are less pronounced, however. [ABSTRACT FROM AUTHOR]