Particle decay of proton-unbound levels in N 12

Background: Transfer reactions are a useful tool for studying nuclear structure, particularly in the regime of low level densities and strong single-particle strengths. In addition, transfer reactions can populate levels above particle decay thresholds, allowing for the possibility of studying the subsequent decays and furthering our understanding of the nuclei being probed. In particular, the decay of loosely bound nuclei such as N12 can help inform and improve structure models. Purpose: To learn about the decay of excited states in N12, to more generally inform nuclear structure models, particularly in the case of particle-unbound levels in low-mass systems which are within the reach of state-of-the-art ab initio calculations. Method: In this follow-up analysis of previously published data [Chipps (JENSA Collaboration), Phys. Rev. C 92, 034325 (2015)]PRVCAN0556-281310.1103/PhysRevC.92.034325, decay particles from excited states populated in N12 have been detected in coincidence with tritons from the N14(p,t)N12 transfer reaction. Specifically, decay protons from proton-unbound levels above ∼2 MeV excitation energy were observed by utilizing the Jet Experiments in Nuclear Structure and Astrophysics (JENSA) gas jet target. Results: Isotropic proton branching ratios for the p0 and p1 decay channels are calculated and decay particle spectra for the populated levels from p0, p1, and p2 decay are given. Conclusions: The current data from N14(p,t)N12 will help provide nuclear structure and decay information input to models in this mass region.