Resonances in 11C observed in the 4He(7Be,α)7Be and 4He(7Be,p)10B reactions

Measurements of the ⁴He(⁷Be,α)⁷Be and ⁴He(⁷Be,p)¹⁰B reactions were performed using ⁷Be beam energies of 7.1 and 23 MeV and a helium-4 target, employing the thick target technique. Resonances were observed between E_x(¹¹C)=8.6 to 13.8 MeV. An R-matrix analysis was performed to characterize the spins and partial widths. This analysis showed that the observed sequence of states was consistent with that found for ⁷Li + α resonant scattering populating resonances in ¹¹B. A comparison of the proposed partial widths for decay with the Wigner limit indicates that several of the states are associated with cluster-like structures.