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Proton-neutron quadrupole interactions: an effective contribution to the pairing field

R. Fossion·C. De Coster·J. E. Garcia-Ramos·K. Heyde
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Abstract

We point out that the proton-neutron energy contribution, for low multipoles (in particular for the quadrupole component), effectively renormalizes the strength of the pairing interaction acting amongst identical nucleons filling up a single-j or a set of degenerate many-j shells. We carry out the calculation in lowest-order perturbation theory. We perform a study of this correction in various mass regions. These results may have implications for the use of pairing theory in medium-heavy nuclei and for the study of pairing energy corrections to the liquid drop model when studying nuclear masses.

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R. Fossion, C. De Coster, J. E. Garcia-Ramos, K. Heyde. 2002-01-22. Proton-neutron quadrupole interactions: an effective contribution to the pairing field. https://doi.org/10.1103/physrevc.65.044309

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