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Roles of triaxiality and residual interaction in signature inversions of A~130 odd-odd nuclei

N. Tajima
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Abstract

Rotational bands with (neutron h_11/2)^1 (proton h_11/2)^1 configurations are studied using a particle-rotor model in which a proton and a neutron quasiparticles interacting through a zero-range force are coupled with a triaxial rotor. It is shown for 124Cs that one can reproduce the signature dependence of energy and B(M1)/B(E2) ratio best when one takes into account gamma-deformations with irrotational-flow moment of inertia in addition to the proton-neutron interaction proposed by Semmes and Ragnarsson. Including both effects, a systematic calculation of signature splittings is performed for Cs, La isotopes and N=75 isotones to be compared with experiments. Discussions are also done on the deficiencies of the cranking model concerning its applicability to signature inversion phenomena in odd-odd nuclei.

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N. Tajima. 1993-09-08. Roles of triaxiality and residual interaction in signature inversions of A~130 odd-odd nuclei. https://doi.org/10.1016/0375-9474(94)90180-5

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