Inelastic scattering from12 C has been measured at the extremely forward angles including 0• using 386 MeV α particles to study the α-cluster states around Ex ∼ 10 MeV, especially the 2 + state predicted by the α-cluster model. We have analyzed the (α,α ′ ) cross-section data using both the peak-fitting and the multipole decomposition techniques. A 2 + state at Ex = 9.84 ± 0.06 MeV with a width of 1.01 ± 0.15 MeV is found to be submerged in the broad 0 + state at Ex = 9.93 ± 0.03 MeV with a width of 2.71 ± 0.08 MeV. This 2 + state may be interpreted as the 2 + excitation of the Hoyle state and the α-condensate state.

Multipole strength distributions for isoscalar L ≤ 2 transitions in 28 Si have been extracted using 386-MeV inelastic α scattering at extremely forward angles, including 0• . Observed strength distributions are in good agreement with microscopic calculations for an oblate-deformed ground-state. In particular, a large peak at an excitation energy of 17.7 MeV in the isoscalar giant monopole resonance (ISGMR) strength is consistent with the calculations.

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The isoscalar giant monopole resonance (ISGMR) strength distribution in 24 Mg has been determined from background-free inelastic scattering of 386-MeV α particles at extreme forward angles, including 0 • .