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Attractive and repulsive contributions of medium fluctuations to nuclear superfluidity

G. Gori·F. Ramponi·F. Barranco·P. F. Bortignon·R. A. Broglia·G. Colo'·E. Vigezzi
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Abstract

Oscillations of mainly surface character (S=0 modes) give rise, in atomic nuclei, to an attractive (induced) pairing interaction, while spin (S=1) modes of mainly volume character generate a repulsive interaction, the net effect being an attraction which accounts for a sizeable fraction of the experimental pairing gap. Suppressing the particle-vibration coupling mediated by the proton degrees of freedom, i.e., mimicking neutron matter, the total surface plus spin-induced pairing interaction becomes repulsive.

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G. Gori, F. Ramponi, F. Barranco, P. F. Bortignon, R. A. Broglia, G. Colo', E. Vigezzi. 2005-02-23. Attractive and repulsive contributions of medium fluctuations to nuclear superfluidity. https://doi.org/10.1103/physrevc.72.011302

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