High-spin states with seniority v=4,4,6 in 119-126Sn

Abstract

The 119-126Sn nuclei have been produced as fission fragments in two reactions induced by heavy ions: 12C+238U at 90 MeV bombarding energy, 18O+208Pb at 85 MeV. Their level schemes have been built from gamma rays detected using the Euroball array. High-spin states located above the long-lived isomeric states of the even- and odd-A 120-126Sn nuclei have been identified. Moreover isomeric states lying around 4.5 MeV have been established in 120,122,124,126Sn from the delayed coincidences between the fission fragment detector SAPhIR and the Euroball array. The states located above 3-MeV excitation energy are ascribed to several broken pairs of neutrons occupying the nu h11/2 orbit. The maximum value of angular momentum available in such a high-j shell, i.e. for mid-occupation and the breaking of the three neutron pairs, has been identified. This process is observed for the first time in spherical nuclei.

20 pages, 22 figures, 12 tables, accepted for publication in Physical Review C

References in corpus (1)

• Seniority in quantum many-body systems

Cited by in corpus (7)

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• Overview of Seniority Isomers
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• Systematic shell model study for $N=82$ and $N=126$ isotones and nuclear isomers
• Systematic shell-model study of Rn isotopes with $A=$ 207 to 216 and isomeric states
• $\Delta v=2$ seniority changing transitions in yrast $3^{-}$ states and B(E3) systematics of Sn isotopes
• Prompt-delayed $\gamma$-ray spectroscopy of neutron-rich ${}^{119,121}$In isotopes