Spin-flip strength in the 20-28 MeV region of excitation inC12and the extended coupled-channels model predictions

Abstract

The spin-flip strength distribution in the 20 to 28 MeV excitation in $^{12}\mathrm{C}$ deduced from a recent study of the $^{12}\mathrm{C}({\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}, {{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}}^{\ensuremath{'}})$ reaction is discussed in the context of an earlier coupled-channel analysis of the $^{11}\mathrm{B}(\mathrm{p}, {\ensuremath{\gamma}}_{1})$ reaction data. It is shown that a good correspondence can be established between certain broad resonances observed in the two types of reactions not only with regard to the energy but also the width. Definitive spin, isospin, and parity assignments can be made on the basis of this comparison.