Effects of one valence proton on seniority and angular momentum of neutrons in neutron-rich $^{122-131}$Sb$_{51}$ isotopes
Creators: name: Biswas, S.
name: Lemasson, A.
name: Rejmund, M.
name: Navin, A.
name: Kim, Y. H.
name: Michelagnoli, C.
name: Stefan, I.
name: Banik, R.
name: Bednarczyk, P.
name: Bhattacharya, S.
name: Bhattacharyya, S.
name: Clément, E.
name: Crawford, H. L.
name: de France, G.
name: Fallon, P.
name: Frémont, G.
name: Goupil, J.
name: Jacquot, B.
name: Li, H. J.
name: Ljungvall, J.
name: Maj, A.
name: Ménager, L.
name: Morel, V.
name: Palit, R.
name: Pérez-Vidal, R. M.
name: Ropert, J.
name: Barrientos, D.
name: Benzoni, G.
name: Birkenbach, B.
name: Boston, A. J.
name: Boston, H. C.
name: Cederwall, B.
name: Collado, J.
name: Cullen, D. M.
name: Désesquelles, P.
name: Domingo-Pardo, C.
name: Dudouet, J.
name: Eberth, J.
name: Gonzalez, V.
name: Harkness-Brennan, L. J.
name: Hess, H.
name: Jungclaus, A.
name: Korten, W.
name: Labiche, M.
name: Lefevre, A.
name: Menegazzo, R.
name: Mengoni, D.
name: Million, B.
name: Napoli, D. R.
name: Pullia, A.
name: Quintana, B.
name: Ralet, D.
name: Recchia, F.
name: Reiter, P.
name: Saillant, F.
name: Salsac, M. D.
name: Sanchis, E.
name: Stezowski, O.
name: Theisen, Ch.
name: Valiente-Dobon, J. J.
name: Zielinska, M.
Publisher: name: arXiv
Year: 2019
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: The neutron-rich $^{122-131}$Sb isotopes were produced as fission fragments in the reaction $^{9}$Be($^{238}$U,~f) with 6.2 MeV/u beam energy. An unique setup, consisting of AGATA, VAMOS++ and EXOGAM detectors, was used which enabled the prompt-delayed gamma-ray ($γ$) spectroscopy of fission fragments in the time range of 100 ns - 200 $μ$s. New isomers, prompt and delayed transitions were established in the even-A $^{122-130}$Sb isotopes. In the odd-A $^{123-131}$Sb isotopes, new prompt and delayed $γ$-ray transitions were identified, in addition to the confirmation of the previously known isomers. The half-lives of the isomeric states and the $B(E2)$ transition probabilities of the observed transitions depopulating these isomers were extracted. The experimental data was compared with the theoretical results obtained in the framework of Large-Scale Shell-Model (LSSM) calculations in a restricted model space. Modifications of several components of the shell model interaction were introduced to obtain a consistent agreement with the excitation energies and the $B(E2)$ transition probabilities in neutron-rich Sn and Sb isotopes. The isomeric configurations in Sn and Sb were found to be relatively pure. Further, the calculations revealed that the presence of a single valence proton, mainly in the $g_{7/2}$ orbital in Sb isotopes, leads to significant mixing (due to the $νπ$ interaction) of: (i) the neutron seniorities ($\upsilon_ν$) and (ii) the neutron angular momentum ($I_ν$). The above features have a weak impact on the excitation energies, but have an important impact on the $B(E2)$ transition probabilities. In addition, a constancy of the relative excitation energies irrespective of neutron seniority and neutron number in Sn and Sb was observed.
description: 23 pages, 18 figures, 10 tables