The nuclear contacts and short range correlations in nuclei

TL;DR

This paper introduces an effective framework to describe short-range correlations in nuclei using contact terms, enabling extraction from experimental data and comparison with observed high-momentum nucleon pairs.

Contribution

It presents a novel effective approach to characterize short-range nuclear structure through contact terms and asymptotic wave functions, linking theory with experimental observations.

Findings

Identification of high-momentum regions dominated by close-proximity nucleon pairs.

Quantification of short-range correlated nucleon pairs in nuclei.

Observation of non-combinatorial isospin symmetry in SRC pairs.

Abstract

Atomic nuclei are complex strongly interacting systems and their exact theoretical description is a long-standing challenge. An approximate description of nuclei can be achieved by separating its short and long range structure. This separation of scales stands at the heart of the nuclear shell model and effective field theories that describe the long-range structure of the nucleus using a mean- field approximation. We present here an effective description of the complementary short-range structure using contact terms and stylized two-body asymptotic wave functions. The possibility to extract the nuclear contacts from experimental data is presented. Regions in the two-body momentum distribution dominated by high-momentum, close-proximity, nucleon pairs are identified and compared to experimental data. The amount of short-range correlated (SRC) nucleon pairs is determined and compared to measurements. Non-combinatorial isospin symmetry for SRC pairs is identified. The obtained one-body momentum distributions indicate dominance of SRC pairs above the nuclear Fermi-momentum.