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arXiv · 1312.4595

Nuclear shape coexistence: A study of the even-even Hg isotopes using the interacting boson model with configuration mixing

J. E. Garcia-Ramos·K. Heyde
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Abstract

Background: The Po, Pb, Hg, and Pt region is known for the presence of coexisting structures that correspond to different particle-hole configurations in the Shell Model language or equivalently to nuclear shapes with different deformation. Purpose: We intend to study the configuration mixing phenomenon in the Hg isotopes and to understand how different observables are influenced by it. Method: We study in detail a long chain of mercury isotopes, $^{172-200}$Hg, using the interacting boson model with configuration mixing. The parameters of the Hamiltonians are fixed through a least square fit to the known energies and absolute B(E2) transition rates of states up to $3$ MeV. Results: We obtained the IBM-CM Hamiltonians and we calculate excitation energies, B(E2)'s, quadrupole shape invariants, wave functions, isotopic shifts, and mean field energy surfaces. Conclusions: We obtain a fairly good agreement with the experimental data for all the studied observables and we conclude that the Hamiltonian and the states we obtain constitute a good approximation to the Hg isotopes.

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J. E. Garcia-Ramos, K. Heyde. 2013-12-17. Nuclear shape coexistence: A study of the even-even Hg isotopes using the interacting boson model with configuration mixing. https://doi.org/10.1103/physrevc.89.014306

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