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Isomeric states in odd-A tantalum isotopes with N=106–116

A. Kardan1, P. M. Walker2, and A. K. Jain3

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Phys. Rev. C 114, 044328 – Published 20 October, 2026

DOI: https://doi.org/10.1103/r54y-vlpx

Abstract

The structure of high-K isomeric states in the odd-A tantalum (Z=73) isotopes is investigated systematically within the cranked Nilsson–Strutinsky (CNS) and cranked Nilsson–Strutinsky–Bogoliubov (CNSB) frameworks, spanning neutron numbers N=106–116. The low-lying one-proton isomers are identified with the 9/2−[514], 5/2+[402], and 1/2+[411] Nilsson orbitals, while the two-quasineutron configurations Kπ=8−, 10+, and 10− are shown to play a decisive role in driving multiquasiparticle isomer formation across the chain. High-K isomers are predicted in Ta189 at low excitation energies, presenting a strong motivation for future experiments. The CNSB calculations predict a transition from stable prolate shapes to triaxiality and shape coexistence in odd-A Ta isotopes near N=114–116.

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Phys. Rev. C 114, 044328– Published 20 October, 2026
  • Received 18 July 2026
  • Accepted 2 October 2026
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