The evidence of $N=16$ shell closure and $\beta$-delayed neutron emission from $^{25}$F

J. F. Peltier; Z. Y. Xu; I. Cox; R. Grzywacz; R. S. Lubna; N. Kitamura; S. Neupane; J. M. Allmond; J. Christie; A. A. Doetsch; P. Dyszel; T. Gaballah; T. T. King; K. Kolos; S. N. Liddick; M. Madurga; T. H. Ogunbeku; B. M. Sherrill; K. Siegl

arXiv · 2412.12071

The evidence of $N=16$ shell closure and $\beta$-delayed neutron emission from $^{25}$F

J. F. Peltier·Z. Y. Xu·I. Cox·R. Grzywacz·R. S. Lubna·N. Kitamura·S. Neupane·J. M. Allmond·J. Christie·A. A. Doetsch·P. Dyszel·T. Gaballah·T. T. King·K. Kolos·S. N. Liddick·M. Madurga·T. H. Ogunbeku·B. M. Sherrill·K. Siegl

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Abstract

We measured the $\beta$-delayed neutron emission from $^{25}$F for the first time at the Facility for Rare Isotope Beams (FRIB). Using combined neutron and $\gamma$-ray detector systems of the FRIB Decay Station Initiator (FDSi), we observed $\beta$-decay transitions populating neutron unbound states between 4.2 and 8 MeV in $^{25}$Ne. The experimental results led to the revision of the $\beta$-decay half-life and $\beta$-delayed neutron-emission probability of $^{25}$F. The $\beta$-decay strength distribution of $^{25}$F extracted from the data agrees with the shell-model predictions using the USDB and SDPF-M effective interactions. This result indicates that the spherical neutron $N = 16$ shell gap persists in $^{25}$F and $^{25}$Ne.

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J. F. Peltier, Z. Y. Xu, I. Cox, R. Grzywacz, R. S. Lubna, N. Kitamura, S. Neupane, J. M. Allmond, J. Christie, A. A. Doetsch, P. Dyszel, T. Gaballah, T. T. King, K. Kolos, S. N. Liddick, M. Madurga, T. H. Ogunbeku, B. M. Sherrill, K. Siegl. 2024-12-16. The evidence of $N=16$ shell closure and $\beta$-delayed neutron emission from $^{25}$F. https://arxiv.org/abs/2412.12071

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