R -matrix analysis of Ne 22 states populated in O 18 (α,α) resonant elastic scattering

The properties of resonances in the O18+α interaction are important for analyses of astrophysical processes and for understanding of the development of the α-cluster structure with addition of neutrons to 4N nuclei. Previous high-energy resolution measurements have not been treated using the contemporary R-matrix approach. We have performed an R-matrix analysis of the resonant data [D. Powers, J. K. Bair, J. L. C. Ford, Jr., and H. B. Willard, Phys. Rev. 134, B1237 (1964)0031-899X10.1103/PhysRev.134.B1237] and obtained new data on 15 levels in the excitation region of 11.7-12.5 MeV Ne22. It appears that the model calculations did not predict the observed tendency in the Ne20-22 α clustering. This paper is the first step of our program of investigation of the Ne22 spectrum in resonant reactions.