High-spin states with seniority<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi>v</mml:mi><mml:mo>=</mml:mo><mml:mn>4</mml:mn></mml:mrow></mml:math>, 5, and 6 in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msup><mml:mrow/><mml:mrow><mml:mn>119</mml:mn><mml:mo>–</mml:mo><mml:mn>126</mml:mn></mml:mrow></mml:msup></mml:math>Sn

The ${}^{119--126}$Sn nuclei have been produced as fission fragments in two reactions induced by heavy ions: ${}^{12}\text{C}+{}^{238}\text{U}$ at a bombarding energy of 90 MeV and ${}^{18}\text{O}+{}^{208}\text{Pb}$ at 85 MeV. Their level schemes have been built from $\ensuremath{\gamma}$ rays detected using the Euroball array. High-spin states located above the long-lived isomeric states of the even- and odd-$A$ ${}^{120--126}$Sn nuclei have been identified. Moreover, isomeric states lying around 4.5 MeV have been established in ${}^{120,122,124,126}$Sn 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 $\ensuremath{\nu}{h}_{11/2}$ orbit. The maximum value of angular momentum available in such a high-$j$ shell, i.e., for midoccupation and the breaking of the three neutron pairs, has been identified. This process is observed for the first time in spherical nuclei.

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