${}^{21}$Ne level structure in the resonance ${}^{17}$O+$\alpha$ elastic scattering

Abstract

The first study of resonances in ${}^{17}$O+$\alpha$ elastic scattering was carried out using the Thick Target Inverse Kinematics (TTIK) method. The data were analyzed in the framework of an $\text{R}$-matrix approach. Many $\alpha$-cluster states were found in the ${}^{21}$Ne excitation region of the 9-13 MeV excitation energy including the first observation of a broad $\text{l}$=0 state in an odd-even nucleus, which is likely the analog of the broad 0${}^{+}$ at 8 MeV in ${}^{20}$Ne. The observed structure in ${}^{21}$Ne appeared to be strikingly similar to that in ${}^{20}$Ne populated in the resonance ${}^{16}$O+$\alpha$ scattering. The results are also useful for refinement of data on an ${}^{17}$O($\alpha$,$\text{n}$) reaction important for astrophysics.