https://doi.org/10.1051/epjconf/202532400026
A unified description of the shape phase transition, shape coexistence and mixing phenomena in nuclei
1 "Horia Hulubei" - National Institute for R&D in Physics and Nuclear Engineering, St. Reactorului no. 30, RO-077125, POB-MG6, Bucharest-Magurele, Romania
2 Academy of Romanian Scientists. St. Splaiul Independentei no. 54, RO-050044, Bucharest, Romania
* e-mail: buganu@theory.nipne.ro
Published online: 11 April 2025
The shape phase transition, shape coexistence and mixing phenomena can be described in a unified way within the framework of the phenomenological Bohr-Mottelson model involving a sixth order anharmonic oscillator potential in the intrinsic deformation variable. This potential can have alternatively, depending on its parameters, a single spherical minimum, a single deformed minimum, a flat shape and simultaneously spherical and deformed minima, respectively. Thus, an entire phase transition from a spherical shape to a deformed one can be covered, crossing the critical point where the potential is flat (second order phase transition) or it has a small barrier (first order phase transition), while the shape coexistence and mixing phenomena emerge by simply increasing the barrier in the critical point. The type of axial deformations (prolate, triaxial, γ-unstable) are given here by the additional degree of freedom γ in relation to the γ potential shape.
© The Authors, published by EDP Sciences, 2025
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
