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arXiv · 1712.03705

Davydov-Chaban Hamiltonian with deformation-dependent mass term for γ = 30°

P. Buganu·M. Chabab·A. El Batoul·A. Lahbas·M. Oulne
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Abstract

Motivation : Several theoretical comparisons with experimental data have recently pointed out that the mass tensor of the collective Bohr Hamiltonian cannot be considered as a constant and should be taken as a function of the collective coordinates. Method : The Davydov-Chaban Hamiltonian, describing the collective motion of γ-rigid atomic nuclei, is modified by allowing the mass to depend on the nuclear deformation. Moreover, the eigenvalue problem for this Hamiltonian is solved for Davidson potential and γ = 30° involving an Asymptotic Iteration Method (AIM). The present model is conventionally called Z(4)-DDM-D (Deformation Dependent Mass with Davidson potential), in respect to the so called Z(4) model. Results : Exact analytical expressions are derived for energy spectra and normalized wave functions, for the present model. The obtained results show an overall agreement with the experimental data for 108-116Pd, 128-132Xe, 136;138Ce and 190-198Pt and an important improvement in respect to other models. Prediction of a new candidate nucleus for triaxial symmetry is made. Conclusion : The dependence of the mass on the deformation reduces the increase rate of the moment of inertia with deformation, removing a main drawback of the model and leading to an improved agreement with the corresponding experimental data.

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P. Buganu, M. Chabab, A. El Batoul, A. Lahbas, M. Oulne. 2017-12-11. Davydov-Chaban Hamiltonian with deformation-dependent mass term for γ = 30°. https://doi.org/10.1016/j.nuclphysa.2017.12.001

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