Study of the beta-delayed alpha-particle emission ofN16

The beta-delayed alpha-particle emission of ${}_{}{}^{16}{}_{}{}^{}\mathrm{N}$ has been studied, with ${}_{}{}^{16}{}_{}{}^{}\mathrm{N}$ nuclei produced using 80 MeV/nucleon ${}_{}{}^{18}{}_{}{}^{}\mathrm{O}$ beams on ${}_{}{}^9{}_{}{}^{}\mathrm{Be}$ targets. The ${}_{}{}^{16}{}_{}{}^{}\mathrm{N}$ secondary nuclei were mass analyzed and separated from the reaction products using the Michigan State University A1200 isotope separator. A detector array, including four thin surface barrier detectors, a p-i-n diode, a Ge gamma-ray detector, and a two-dimensional position sensitive parallel plate avalanche counter, was used for implantation and study of the separated nuclei. A beta-decay branching ratio of (1.3±0.3)×${10}^{\mathrm{-}5}$ to the $1^{\mathrm{-}}$ state at 9.6 MeV and a centroid of 2.35±0.05 MeV for the beta-delayed alpha-particle emission were measured. These results are essential for the analysis of a high sensitivity measurement at Yale University of the low-energy beta-delayed alpha-particle emission of ${}_{}{}^{16}{}_{}{}^{}\mathrm{N}$, and for understanding the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$(α,γ${)}^{16}$O reaction in the helium burning process in massive stars.