Two-proton correlations in the decay of 48Ni and 45Fe

A. Ortega Moral; S. M. Wang; J. Giovinazzo; T. Roger; B. Blank; P. Ascher; C. Borcea; L. Caceres; M. Caamano; F. de Oliveira Santos; A. de Roubin; B. Fernandez-Dominguez; D. Fernandez-Dominguez; J. Lois-Fuentes; M. Gerbaux; S. Grevy; M. Hukkanen; A. Husson; O. Kamalou; T. Kurtukian-Nieto; J. Michaud; J. Pancin; J. Piot; M. Pomorski; D. Regueira-Castro; A. M. Sanchez-Benitez; O. Sorlin; M. Stanoiu; C. Stodel; J. -C. Thomas; M. Vandebrouck

arXiv · 2504.14607

Two-proton correlations in the decay of 48Ni and 45Fe

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Abstract

The main observables of the rare two-proton emission process - half-life, total energy of the decay as well as energy and angular correlations between the emitted protons - have been measured for 48Ni and 45Fe in a recent experiment performed at the GANIL/LISE3 facility. The results, together with previous experimental work, are compared for the first time with calculations performed in the recently developed Gamow Coupled-Channel (GCC) framework and to 3-body predictions from literature. The comparison of the 48Ni and the 45Fe two-proton angular distributions with the GCC calculations confirms the adopted strength of the proton-proton interaction for both nuclei and the predominant small-angle emission. A comparison with 3-body model angular distributions indicates the shell closure of the f_7/2 orbital for 48Ni and a substantial occupancy of the p-orbital for 45Fe. Discrepancies between experimental data and theoretical predictions are found when studying the other observables: half-lives, total energy of the decay and energy correlations, showing the complexity of the description of the two-proton emission process.

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A. Ortega Moral, S. M. Wang, J. Giovinazzo, T. Roger, B. Blank, P. Ascher, C. Borcea, L. Caceres, M. Caamano, F. de Oliveira Santos, A. de Roubin, B. Fernandez-Dominguez, D. Fernandez-Dominguez, J. Lois-Fuentes, M. Gerbaux, S. Grevy, M. Hukkanen, A. Husson, O. Kamalou, T. Kurtukian-Nieto, J. Michaud, J. Pancin, J. Piot, M. Pomorski, D. Regueira-Castro, A. M. Sanchez-Benitez, O. Sorlin, M. Stanoiu, C. Stodel, J. -C. Thomas, M. Vandebrouck. 2025-04-20. Two-proton correlations in the decay of 48Ni and 45Fe. https://arxiv.org/abs/2504.14607

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