C. E. Alonso

U(5)-O(6) transition in the interacting boson model and the E(5) critical point symmetry

The relation of the recently proposed

DESCRIPTION OF THE ODD-EVEN XENON AND CESIUM ISOTOPES IN THE PROTON-NEUTRON INTERACTING BOSON-FERMION MODEL

E(5)

Prealignment B(E2)-anomaly in 124Xe

critical point symmetry with the interacting boson model is investigated. The large-

Critical-point symmetries in boson-fermion systems: the case of shape transitions in odd nuclei in a multiorbit model.

N

Nuclear structure studies of the odd-mass Ba and La isotopes with the IBFA-2 model

limit of the interacting boson model at the critical point in the transition from U(5) to O(6) is obtained by solving the Richardson equations. It is shown explicitly that this algebraic calculation leads to the same results as the solution of the Bohr differential equation with a

Backbending of Dy isotopes described with the neutron-photon IBA plus two-quasiparticle model

{\ensuremath{\beta}}^{4}

Phase transitions in the interacting boson fermion model: The γ -unstable case

potential.

Description of octupole-deformed nuclei within the interacting boson and interacting boson-fermion models

Abstract We present the results of a study of the properties of both negative- and positive-parity states in odd-proton Cs and odd-neutron Xe isotopes within the framework of the proton-neutron interacting boson-fermion model (IBFA-2). We show that within IBFA-2 a unified description of long odd- A isotopic chains, including isospin effects, can be given.

Intrinsic frame description of interacting boson-fermion systems

Lifetimes of 17 levels of 124Xe were measured using the Recoil Distance Doppler Shift method. An anomalous E2-reduction was observed, starting at Iπ = 8+ and Iπ = 5+ in the groundstate and in the quasi-gamma band respectively. This anomaly is discussed in terms of the Interacting Boson Model.

Odd-even nuclei in the A ≈ 100 nuclear region☆

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 gamma-unstable behavior. 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.