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arXiv · 1408.5985

Shell-gap reduced level densities in $^{89,90}$Y

M. Guttormsen·A. C. Larsen·F. L. Bello Garrote·Y. Byun·T. K. Eriksen·F. Giacoppo·A. Görgen·T. W. Hagen·M. Klintefjord·H. T. Nyhus·T. Renstrøm·S. J. Rose·E. Sahin·S. Siem·T. Tornyi·G. M. Tveten·A. Voinov
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Abstract

Particle-$γ$ coincidences from the $^{89}$Y($p,p' γ$)$^{89}$Y and $^{89}$Y($d,p γ$)$^{90}$Y reactions were utilized to obtain $γ$-ray spectra as function of excitation energy. The Oslo method was used to extract the level density from the particle-$γ$ coincidence matrices. The impact of the $N=50$ shell closure on the level densities is discussed within the framework of a combinatorial quasi-particle model.

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M. Guttormsen, A. C. Larsen, F. L. Bello Garrote, Y. Byun, T. K. Eriksen, F. Giacoppo, A. Görgen, T. W. Hagen, M. Klintefjord, H. T. Nyhus, T. Renstrøm, S. J. Rose, E. Sahin, S. Siem, T. Tornyi, G. M. Tveten, A. Voinov. 2014-08-26. Shell-gap reduced level densities in $^{89,90}$Y. https://doi.org/10.1103/physrevc.90.044309

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