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Critical point symmetries in boson-fermion systems. The case of shape transition in odd nuclei in a multi-orbit model

C. E. Alonso·J. M. Arias·A. Vitturi
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Abstract

We investigate phase transitions in boson-fermion systems. We propose an analytically solvable model (E(5/12)) to describe odd nuclei at the critical point in the transition from the spherical to $γ$-unstable behaviour. In the model, a boson core described within the Bohr Hamiltonian interacts with an unpaired particle assumed to be moving in the three single particle orbitals j=1/2,3/2,5/2. Energy spectra and electromagnetic transitions at the critical point compare well with the results obtained within the Interacting Boson Fermion Model, with a boson-fermion Hamiltonian that describes the same physical situation.

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C. E. Alonso, J. M. Arias, A. Vitturi. 2007-01-08. Critical point symmetries in boson-fermion systems. The case of shape transition in odd nuclei in a multi-orbit model. https://doi.org/10.1103/physrevlett.98.052501

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