We present an experimental study of /sup 19/Na states in the excitation energy range between 2 and 3 MeV. The presence of /sup 19/Na single-particle levels at these energies was first predicted by a microscopic cluster model and then experimentally confirmed by measuring the elastic and inelastic scattering of a 66 MeV /sup 18/Ne radioactive beam on a (CH/sub 2/)n target. The H(/sup 18/Ne, p)/sup 18/Ne(g.s.) and H(/sup 18/Ne, p')/sup 18/Ne*(2/sup +/,1.887 MeV) cross sections have been obtained in the laboratory angular range thetas /sub lab/=6.1 degrees -18.4 degrees and analyzed by using the R-matrix method. Two new states in /sup 19/Na have been observed at centre-of-mass energies E/sub c.m./=2.78+/-0.01 MeV and 3.09+/-0.05 MeV. Both resonances exhibit large widths in the /sup 18/Ne(2/sup +/)+p channel, and low branching ratios into the elastic channel. The reduced proton widths confirm the single-particle nature of these states, with a /sup 18/Ne(2/sup +/)+p structure. [All rights reserved Elsevier].
Pellegriti, M. G., Achouri, N. L., Angulo, C., Angelique, J.-C., Berthoumieux, E., Casarejos, E., Couder, M., Davinson, T., Ghag, C., Murphy, A. S., Orr, N. A., Ray, I., Stefan, I. G., & Descouvemont, P. (2008). Evidence for core excitation in single-particle states of /sup 19/Na. Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics, 659(5), 864-869. https://doi.org/10.1016/j.physletb.2007.12.017 (Original work published 2008)