Universality of nucleon short-range behavior with chiral forces

TL;DR

This paper introduces a new method to analyze nucleon short-range behavior that reveals universal features across different nuclear forces, overcoming limitations of traditional approaches.

Contribution

A novel SRG-independent framework for nuclear wave functions is developed, enabling the study of universal short-range nucleon correlations across various chiral forces.

Findings

The np S=1 two-body density ratio to the deuteron is interaction-insensitive.

The ratio of total two-body densities to the deuteron depends on cutoff, but to the alpha particle it does not.

Universal short-range features are identified in nuclear densities regardless of interaction details.

Abstract

Modern advanced nuclear ab initio approaches with the similarity renormalization group (SRG) softened interactions miss high-momentum information, thus rendering them less suitable for characterizing nucleon-nucleon short-range physics. We introduce a novel framework to construct SRG-independent nuclear wave functions from No-Core Shell Model calculations. Applying our method to densities obtained with semilocal momentum-space-regularized chiral NN and NNN forces, we show key universalities of short-range behavior: (1) The two-body density ratio in the np S=1 channel, relative to the deuteron (d), is remarkably insensitive to interaction details. (2) More strikingly, while the ratio of total two-body densities to the deuteron exhibits cutoff dependence, the same ratio to the $\alpha$-particle (4-He) is almost independent of the interactions.