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Interrelation between the isoscalar octupole phonon and the proton-neutron mixed-symmetry quadrupole phonon in near spherical nuclei

Nadya A. Smirnova·Norbert Pietralla·Takahiro Mizusaki·Piet Van Isacker
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Abstract

The interrelation between the octupole phonon and the low-lying proton-neutron mixed-symmetry quadrupole phonon in near-spherical nuclei is investigated. The one-phonon states decay by collective E3 and E2 transitions to the ground state and by relatively strong E1 and M1 transitions to the isoscalar 2+ state. We apply the proton-neutron version of the Interacting Boson Model including quadrupole and octupole bosons (sdf-IBM-2). Two F-spin symmetric dynamical symmetry limits of the model, namely the vibrational and the γ-unstable ones, are considered. We derive analytical formulae for excitation energies as well as B(E1), B(M1), B(E2) and B(E3) values for a number of transitions between low-lying states.

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Nadya A. Smirnova, Norbert Pietralla, Takahiro Mizusaki, Piet Van Isacker. 2000-06-10. Interrelation between the isoscalar octupole phonon and the proton-neutron mixed-symmetry quadrupole phonon in near spherical nuclei. https://doi.org/10.1016/s0375-9474(00)00331-6

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