The phase anomaly for elastic and inelastic scattering of the 19F + 12C system

The elastic and inelastic scattering of ¹²C from ¹⁹F leading to the $\text{1}\text{2}{}^{\mathrm{+}}\text{(}\text{gs}\text{),}\text{5}\text{2}{}^{\mathrm{+}}\text{(197}\text{keV}\text{),}\text{3}\text{2}{}^{\mathrm{+}}\text{(1.554}\text{MeV}\text{)}$ and $\text{9}\text{2}{}^{\mathrm{+}}\text{(2.780}\text{MeV}$) states has been studied at $\text{E(}{}^{12}\text{C}\text{)=30?60}\text{MeV}$. The angular distributions for the $\text{5}\text{2}{}^{\mathrm{+}}\text{and}\text{3}\text{2}{}^{\mathrm{+}}$ transitions are almost in phase with those of the elastic scattering and cannot be reproduced with the DWBA and CC caculation using collective form factors.