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arXiv · 1406.3610

Probing Nuclear forces beyond the drip-line using the mirror nuclei $^{16}$N and $^{16}$F

I. Stefan·F. de Oliveira Santos·O. Sorlin·T. Davinson·M. Lewitowicz·G. Dumitru·J. C. Angélique·M. Angélique·E. Berthoumieux·C. Borcea·R. Borcea·A. Buta·J. M. Daugas·F. De Grancey·M. Fadil·S. Grévy·J. Kiener·A. Lefebvre-Schuhl·M. Lenhardt·J. Mrazek·F. Negoita·D. Pantelica·M. G. Pellegriti·L. Perrot·M. Ploszajczak·O. Roig·M. G. Saint Laurent·I. Ray·M. Stanoiu·C. Stodel·V. Tatischeff·J. C. Thomas
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Abstract

Radioactive beams of $^{14}$O and $^{15}$O were used to populate the resonant states 1/2$^+$, 5/2$^+$ and $0^-,1^-,2^-$ in the unbound $^{15}$F and $^{16}$F nuclei respectively by means of proton elastic scattering reactions in inverse kinematics. Based on their large proton spectroscopic factor values, the resonant states in $^{16}$F can be viewed as a core of $^{14}$O plus a proton in the 2s$_{1/2}$ or 1d$_{5/2}$ shell and a neutron in 1p$_{1/2}$. Experimental energies were used to derive the strength of the 2s$_{1/2}$-1p$_{1/2}$ and 1d$_{5/2}$-1p$_{1/2}$ proton-neutron interactions. It is found that the former changes by 40% compared with the mirror nucleus $^{16}$N, and the second by 10%. This apparent symmetry breaking of the nuclear force between mirror nuclei finds explanation in the role of the large coupling to the continuum for the states built on an $\ell=0$ proton configuration.

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I. Stefan, F. de Oliveira Santos, O. Sorlin, T. Davinson, M. Lewitowicz, G. Dumitru, J. C. Angélique, M. Angélique, E. Berthoumieux, C. Borcea, R. Borcea, A. Buta, J. M. Daugas, F. De Grancey, M. Fadil, S. Grévy, J. Kiener, A. Lefebvre-Schuhl, M. Lenhardt, J. Mrazek, F. Negoita, D. Pantelica, M. G. Pellegriti, L. Perrot, M. Ploszajczak, O. Roig, M. G. Saint Laurent, I. Ray, M. Stanoiu, C. Stodel, V. Tatischeff, J. C. Thomas. 2014-06-13. Probing Nuclear forces beyond the drip-line using the mirror nuclei $^{16}$N and $^{16}$F. https://doi.org/10.1103/physrevc.90.014307

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