https://doi.org/10.1140/epja/s10050-026-01801-y
Regular Article - Theoretical Physics
Intermediate particle-core coupling in reflection asymmetric odd mass nuclei
1
“Horia Hulubei” National Institute for R&D in Physics and Nuclear Engineering, Str. Reactorului 30, 077125, Bucharest, Romania
2
Academy of Romanian Scientists, Splaiul Independenţei 54, 050044, Bucharest, Romania
a
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Received:
8
December
2025
Accepted:
28
January
2026
Published online:
18
February
2026
Abstract
A coupling scheme between a collective core, with quadrupole and octupole deformation, and a single-particle spin is proposed to describe the complex distribution of the negative and positive parity states in odd mass nuclei. The model is based on an axially symmetric quadrupole-octupole geometric Hamiltonian with an adjustable particle-core coupling, offering a wide range of spectroscopic structures. A specific instance of the model, involving a moderate coupling strength, is identified in 
Ce, 
Nd, 
Ra and 
Th nuclei, respectively discussed in terms of energy levels and relevant electric transitions.
Communicated by Takashi Nakatsukasa.
© The Author(s) 2026
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