학술논문
Dipole and quadrupole moments of $^{73-78}$Cu as a test of the robustness of the $Z=28$ shell closure near $^{78}$Ni
Document Type
Working Paper
Author
de Groote, R. P.; Billowes, J.; Binnersley, C. L.; Bissell, M. L.; Cocolios, T. E.; Goodacre, T. Day; Farooq-Smith, G. J.; Fedorov, D. V.; Flanagan, K. T.; Franchoo, S.; Ruiz, R. F. Garcia; Koszorús, Á.; Lynch, K. M.; Neyens, G.; Nowacki, F.; Otsuka, T.; Rothe, S.; Stroke, H. H.; Tsunoda, Y.; Vernon, A. R.; Wendt, K. D. A.; Wilkins, S. G.; Xu, Z. Y.; Yang, X. F.
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Subject
Language
Abstract
Nuclear spins and precise values of the magnetic dipole and electric quadrupole moments of the ground-states of neutron-rich $^{76-78}$Cu isotopes were measured using the Collinear Resonance Ionization Spectroscopy (CRIS) experiment at ISOLDE, CERN. The nuclear moments of the less exotic $^{73,75}$Cu isotopes were re-measured with similar precision, yielding values that are consistent with earlier measurements. The moments of the odd-odd isotopes, and $^{78}_{29}$Cu ($N=49$) in particular, are used to investigate excitations of the assumed doubly-magic $^{78}$Ni core through comparisons with large-scale shell-model calculations. Despite the narrowing of the $Z=28$ shell gap between $N\sim45$ and $N=50$, the magicity of $Z=28$ and $N=50$ is restored towards $^{78}$Ni. This is due to weakened dynamical correlations, as clearly probed by the present moment measurements.