Shape phase transitions and critical points
|Author||Alonso Alonso, Clara Eugenia
Arias Carrasco, José Miguel
|Department||Universidad de Sevilla. Departamento de Física Atómica, Molecular y Nuclear|
|Published in||6th Japan-Italy Symposium on Heavy-Ion Physics (2009), p 64-69|
|Abstract||We investigate different aspects connected with shape phase transitions in nuclei and the possible occurrence of dynamical symmetries at the critical points. We discuss in particular the behaviour of the neighbour odd ...
We investigate different aspects connected with shape phase transitions in nuclei and the possible occurrence of dynamical symmetries at the critical points. We discuss in particular the behaviour of the neighbour odd nuclei at the vicinity of the critical points in the even nuclei. We consider both the case of the transition from the vibrational behaviour to the gamma-unstable deformation (characterized within the collective Bohr hamiltonian by the E(5) critical point symmetry) and the case of the transition from the vibrational behaviour to the stable axial deformation (characterized by the X(5) symmetry). The odd particle is assumed to be moving in the three single particle orbitals j=1/2,3/2,5/2, a set of orbitals that is known to lead to possible supersymmetric cases. The coupling of the odd particle to the Bohr hamiltonian does lead in fact in the former case at the critical point to the E(5/12) boson-fermion dynamical symmetry. An alternative approach to the two shape transitions is based on the Interacting Boson Fermion Model. In this case suitably parametrized boson-fermion hamiltonians can describe the evolution of the odd system along the shape transitions. At the critical points both energy spectra and electromagnetic transitions were found to display characteristic patterns similar to those displayed by the even nuclei at the corresponding critical point. The behaviour of the odd nuclei can therefore be seen as necessary complementary signatures of the occurrence of the phase transitions.
|Cite||Alonso Alonso, C.E., Arias Carrasco, J.M., Fortunato, L. y Vitturi, A. (2009). Shape phase transitions and critical points. En 6th Japan-Italy Symposium on Heavy-Ion Physics (64-69), Tokio, Japón: American Institute of Physics.|