Low-energy states in 11N and two-proton emission of ~12O

摘要

We have investigated the low-energy states of 11N by the elastic scattering method in inverse kinematics using a 10C beam and a (CD2)n target. Recoil protons were detected at 16 laboratory angles θ_lab = 4.6° – 18.9° in a △E – E detector system. Using the R-matrix method to analyse the 10C + p elastic cross sections, we found 11N to be unbound with respect to proton emission by 1.54±0.02 MeV with a decay width of 0.83±0.03. These results are used to calculate the two-proton decay width of the 12O ground state.