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arXiv · 1108.5100

Semi-microscopic description of the backbending phenomena in some deformed even-even nuclei

A. A. Raduta·R. Budaca
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Abstract

The mechanism of backbending is semi-phenomenologically investigated based on the hybridization of two rotational bands. These bands are defined by treating a model Hamiltonian describing two interacting subsystems: a set of particles moving in a deformed mean field and interacting among themselves through an effective pairing force and a phenomenological deformed core whose intrinsic ground state is an axially symmetric coherent boson state. The two components interact with each other by a quadrupole-quadrupole and a spin-spin interaction. The total Hamiltonian is considered in the space of states with good angular momentum, projected from a quadrupole deformed product function. The single-particle factor function defines the nature of the rotational bands, one corresponding to the ground band in which all particles are paired and another one built upon a $i_{13/2}$ neutron broken pair. The formalism is applied to six deformed even-even nuclei, known as being good backbenders. Agreement between theory and experiment is fairly good.

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A. A. Raduta, R. Budaca. 2011-08-25. Semi-microscopic description of the backbending phenomena in some deformed even-even nuclei. https://doi.org/10.1103/physrevc.84.044323

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