Pairing and short-range correlations in nuclear systems

TL;DR

This paper investigates how short-range correlations affect the pairing gap in nuclear matter, showing significant reductions across different channels using chiral interactions, with implications for nuclear structure and astrophysics.

Contribution

It provides a detailed analysis of the impact of short-range correlations on pairing gaps in nuclear matter using phase-shift equivalent and chiral interactions, highlighting a consistent reduction effect.

Findings

Short-range correlations reduce the pairing gap in all studied channels.

In the triplet nuclear matter channel, correlations cause about a 50% gap reduction.

The results show minimal dependence on the specific NN force used.

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.