Properties of $K^{\pi }=0_1^{+}$, $K^{\pi }=2^{-}$, and $K^{\pi }=0_1^{-}$ bands of ${}^{20}$Ne probed via proton and alpha inelastic scattering

Abstract

The $K^{\pi }=0_1^{+}$, $K^{\pi }=2^{-}$, and $K^{\pi }=0_1^{-}$ bands of ${}^{20}$Ne are investigated with microscopic structure and reaction calculations via proton and $\alpha$ inelastic scattering off ${}^{20}$Ne. Structures of ${}^{20}$Ne are calculated with variation after parity and total angular momentum projections in the antisymmetrized molecular dynamics(AMD). The $K^{\pi }=0_1^{+}$ and $K^{\pi }=0_1^{-}$ bands have ${}^{16}\text{O}+\alpha$ cluster structures, whereas the $K^{\pi }=2^{-}$ band shows a ${}^{12}\text{C}+2\alpha$-like structure. Microscopic coupled-channel calculations of proton and $\alpha$ scattering off ${}^{20}$Ne are performed by using the proton-nucleus and $\alpha$-nucleus potentials, which are derived by folding the Melbourne $g$-matrix $NN$ interaction with AMD densities of ${}^{20}$Ne. The calculation reasonably reproduces the observed cross sections of proton scattering at $E_p=25$--35 MeV and $\alpha$ scattering at $E_{\alpha }=104$--386 MeV. Transition properties from the ground to excited states are discussed by reaction analyses of proton and $\alpha$ inelastic processes. Mixing of the $K^{\pi }=2^{-}$ and $K^{\pi }=0_1^{-}$ bands is discussed by detailed analysis of the $0_1^{+}\to 3_1^{-}$ and $0_1^{+}\to 3_2^{-}$ transitions. For the $3_1^{-}$ state, mixing of the $K^{\pi }=0_1^{-}$ cluster component in the $K^{\pi }=2^{-}$ band plays an important role in the transition properties.

Comments: 14 pages, 9 figures