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arXiv · 1707.04140

Pairing and short-range correlations in nuclear systems

Abstract

The structure and density dependence of the pairing gap in infinite matter is relevant for astrophysical phenomena and provides a starting point for the discussion of pairing properties in nuclear structure. Short-range correlations can significantly deplete the available single-particle strength around the Fermi surface and thus provide a reduction mechanism of the pairing gap. Here, we study this effect in the singlet and triplet channels of both neutron matter and symmetric nuclear matter. Our calculations use phase-shift equivalent interactions and chiral two-body and three-body interactions as a starting point. We find an unambiguous reduction of the gap in all channels with very small dependence on the NN force in the singlet neutron matter and the triplet nuclear matter channel. In the latter channel, short range correlations alone provide a 50% reduction of the pairing gap.

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A. Rios, A. Polls, W. H. Dickhoff. 2017-10-26. Pairing and short-range correlations in nuclear systems. https://doi.org/10.1007/s10909-017-1818-7

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