94 research outputs found
Simultaneous description of four positive and four negative parity bands
The extended coherent state model is further extended in order to describe
two dipole bands of different parities. The formalism provides a consistent
description of eight rotational bands. A unified description for spherical,
transitional and deformed nuclei is possible. Projecting out the angular
momentum and parity from a sole state, the band acquires a
magnetic character, while the electric properties prevail for the other band.
Signatures for a static octupole deformation in some states of the dipole bands
are pointed out. Some properties which distinguish between the dipole band
states and states of the same parity but belonging to other bands are
mentioned. Interesting features concerning the decay properties of the two
bands are found. Numerical applications are made for Gd, Yb,
Th, Ra, U and Pu, and the results are
compared with the available data.Comment: 36 pages, 13 figures, 12 table
Remarks on monopole charge properties within the Generalized Coherent State Model
The Generalized Coherent State Model, proposed previously for a unified
description of magnetic and electric collective properties of nuclear systems,
is used to study the ground state band charge density as well as the E0
transitions from to . The influence of the nuclear
deformation and of angular momentum projection on the charge density is
investigated. The monopole transition amplitude has been calculated for ten
nuclei. The results are compared with some previous theoretical studies and
with the available experimental data. Our results concerning angular momentum
projection are consistent with those of previous microscopic calculations for
the ground state density. The calculations for the E0 transitions agree quite
well with the experimental data. Issues like how the shape transitions or shape
coexistence are reflected in the behavior are also addressed.Comment: 32 pages, 7 figure
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