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DOE OSTI · 1606256

Neutron-hole strength in N = 81 nuclei

Howard, A. M.·Freeman, Sean J.·Sharp, D. K.·Bloxham, T.·Clark, J. A.·Deibel, C. M.·Kay, B. P.·Parker, P. D.·Schiffer, J. P.·Thomas, J. S.
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Abstract

A systematic study of neutron-hole strength in the N = 81 nuclei 137 Ba, 139 Ce, 141 Nd, and 143 Sm is reported. The single-neutron removal reactions (p,d) and ( 3 He,α) were measured at energies of 23 and 34 MeV, respectively. Spectroscopic factors were extracted from measured cross sections through a distorted-wave Born approximation analysis and centroids of single-particle strength have been established. Here, the change in these centroid energies as a function of proton number have been compared to calculations of the monopole shift for the s 1/2 and h 11/2 orbitals, where the majority of the strength has been observed. Significant fragmentation of strength was observed for the d and g 7/2 orbitals, particularly for the latter orbital which is deeply bound, with summed strengths that indicate a significant amount lies outside of the measured excitation energy range.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICS90 ≤ A ≤ 149direct reactionsnuclear structure & decaysspectroscopic factors & electromagnetic momentstransfer reactions

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Howard, A. M., Freeman, Sean J., Sharp, D. K., Bloxham, T., Clark, J. A., Deibel, C. M., Kay, B. P., Parker, P. D., Schiffer, J. P., Thomas, J. S.. 2020-03-20. Neutron-hole strength in N = 81 nuclei. https://doi.org/10.1103/physrevc.101.034309

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