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

Alonso, C. E.; Arias, J. M.; Vitturi, A.

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

Authors

Alonso, C. E.

Arias, J. M.

Vitturi, A.

Description

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.
Phys. Rev. Lett. (in press)