Nuclear Level Density and $\gamma$-ray Strength Function of $^{67}\mathrm{Ni}$ and the impact on the i-process

V. W. Ingeberg; S. Siem; M. Wiedeking; A. Choplin; S. Goriely; L. Siess; K. J. Abrahams; K. Arnswald; F. Bello Garrote; D. L. Bleuel; J. Cederkäll; T. L. Christoffersen; D. M. Cox; H. De Witte; L. P. Gaffney; A. Görgen; C. Henrich; A. Illana; P. Jones; B. V. Kheswa; T. Kröll; S. N. T. Majola; K. L. Malatji; J. Ojala; J. Pakarinen; G. Rainovski; P. Reiter; M. von Schmid; M. Seidlitz; G. M. Tveten; N. Warr; F. Zeiser

doi:10.1103/physrevc.111.015803

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arXiv · 2307.07153

Nuclear Level Density and $\gamma$-ray Strength Function of $^{67}\mathrm{Ni}$ and the impact on the i-process

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Abstract

Proton-$\gamma$ coincidences from $(\mathrm{d},\mathrm{p})$ reactions between a $^{66}\mathrm{Ni}$ beam and a deuterated polyethylene target have been analyzed with the inverse-Oslo method to find the nuclear level density (NLD) and $\gamma$-ray strength function ($\gamma$SF) of $^{67}\mathrm{Ni}$. The $^{66}\mathrm{Ni}(n,\gamma)$ capture cross section has been calculated using the Hauser-Feshbach model in TALYS using the measured NLD and $\gamma$SF as constraints. The results confirm that the $^{66}\mathrm{Ni}(n,\gamma)$ reaction acts as a bottleneck when relying on one-zone nucleosynthesis calculations. However, the impact of this reaction is strongly dampened in multi-zone models of low-metallicity AGB stars experiencing i-process nucleosynthesis.

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V. W. Ingeberg, S. Siem, M. Wiedeking, A. Choplin, S. Goriely, L. Siess, K. J. Abrahams, K. Arnswald, F. Bello Garrote, D. L. Bleuel, J. Cederkäll, T. L. Christoffersen, D. M. Cox, H. De Witte, L. P. Gaffney, A. Görgen, C. Henrich, A. Illana, P. Jones, B. V. Kheswa, T. Kröll, S. N. T. Majola, K. L. Malatji, J. Ojala, J. Pakarinen, G. Rainovski, P. Reiter, M. von Schmid, M. Seidlitz, G. M. Tveten, N. Warr, F. Zeiser. 2023-07-14. Nuclear Level Density and $\gamma$-ray Strength Function of $^{67}\mathrm{Ni}$ and the impact on the i-process. https://doi.org/10.1103/physrevc.111.015803

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