Interacting Boson Model of Collective Octupole States
نویسندگان
چکیده
We discuss the problem of describing low-lying collective negative-parity states within the framework of the interacting boson model. We suggest that a simultaneous description of quadrupole and octupole states in nuclei be done in terms of the group U(16), which includes fand p-bosons in addition to the usual dand s-bosons. We analyze the dynamical symmetries associated with the rotational limit of this model and discuss their classical (large-N) analogs. We conclude with a preliminary application of the model to the radium isotopes.
منابع مشابه
- th / 9 90 60 15 v 1 5 J un 1 99 9 Studies of the Electric Dipole Transition of Deformed Rare - earth nuclei
Spectrum and electric dipole transition rates and relative intensities in 152−154Sm, 156−160Gd, 160−162Dy are studied in the framework of the interacting boson model with s,p,d,f bosons. It is found that E1 transition data among the low-lying levels are in good agreement with the SU(3) dynamical symmetry of the spdf interacting boson model proposed by Engel and Iachello to describe collective r...
متن کاملMean field study of the quadrupole-octupole degree of freedom in the spdf boson model
We present a mean field study of the quadrupole-octupole degree of freedom in collective nuclei within the framework of the spd f -boson model. For realistic choices of the Hamiltonian parameters, the ground state of the system is shown to remain axially symmetric, which considerably simplifies the mean field treatment. The critical point for the onset of octupole deformation in quadrupole defo...
متن کاملShape-phase transitions in mixed parity systems and the onset of octupole deformation
Shape-phase transitions in mixed parity boson systems are studied using mean field theory. It is shown that without parity projection, shape transitions in mixed parity systems are very similar to those in positive parity systems, both requiring a finite interaction strength for the onset of deformation. The shape-phase diagram in mixed parity systems, however, changes significantly after parit...
متن کاملShape - phase transitions in mixed parity systems and the onset of octupole deformation 1
Shape-phase transitions in mixed parity boson systems are studied using mean field theory. It is shown that without parity projection, shape transitions in mixed parity systems are very similar to those in positive parity systems, both requiring a finite interaction strength for the onset of deformation. The shape-phase diagram in mixed parity systems, however, changes significantly after parit...
متن کاملOctupole correlations in positive-parity states of rare-earth and actinide nu- clei
In this contribution, further evidence of the importance of multiphonon-octupole excitations to describe experimental data in the rare earths and actinides will be presented. First, new results of a (p, t) experiment at the Q3D magnetic spectrograph in Munich will be discussed, which was performed to selectively excite J = 0 states in 240Pu. spd f interacting boson model (IBM) calculations sugg...
متن کامل