A local-density-approximation description of high-momentum tails in isospin asymmetric nuclei

TL;DR

This paper introduces a local density approximation method to incorporate high-momentum tails in the momentum distributions of isospin asymmetric nuclei, aligning theoretical predictions with experimental data.

Contribution

It develops a novel approach combining the local density approximation with high-momentum tail modeling, improving agreement with experimental benchmarks for asymmetric nuclei.

Findings

High-momentum nucleon percentage is about 17-18%, regardless of isospin asymmetry.

Tensor force enhances nucleon-nucleon correlations on the nuclear surface.

The method aligns theoretical high-momentum ratios with experimental observations.

Abstract

We adapt the local density approximation to add the high-momentum tails (HMTs) to finite nuclei's Slater-determinant momentum distributions. The HMTs are extracted by the extended Brueckner-Hartree-Fock (EBHF) method or by the lowest order cluster approximation. With a correction factor being added to EBHF, it is sufficiently in agreement with the experimental benchmark, i.e., the high-momentum $N/Z$ ratios approximately equal to $1$, and the low-momentum $N/Z$ ratios approximately equal to $N/Z$ of the systems. It is also found that the tensor force makes the nucleon-nucleon correlations appear more easily on the nuclear surface region and the percentage of high-momentum ($p > 300$ MeV/c) nucleons, around $17\%$--$18\%$, independent of isospin asymmetry.