$A=2,3,4$ nuclear contact coefficients in the generalized contact formalism

TL;DR

This paper calculates nuclear contact coefficients for A=2,3,4 nuclei using the generalized contact formalism with local and non-local chiral potentials, verifying some predictions and highlighting discrepancies in singlet channels.

Contribution

It extends previous local interaction models by including non-local potentials and analyzes the model-independence of contact coefficient ratios.

Findings

Generalized contact formalism predictions verified in triplet spin channel.

Significant tensions observed in singlet channels with non-local potentials.

Ratios between contact coefficients show good model-independence.

Abstract

We present a theoretical calculation for the $A = 2, 3$ and 4 nuclear contact coefficients within the generalized contact formalism, using both local and non-local chiral potentials. The Hyperspherical Harmonics method is employed to calculate the nuclear wave functions, from which we derive two-body momentum distributions and density functions to extract the contact coefficients. We have extracted the contact coefficients from two-body momentum distributions or from density functions, for a given nucleus and potential, and we have found that the generalized contact formalism predictions are verified in the triplet spin channel for local and non-local potentials. On the other hand, some significant tensions exist for the singlet channels, especially when studied with non-local potentials. We have also analyzed the model-independence of the ratios between the contact coefficients, and we have found to be quite satisfied. This study extends previous works based on local interaction models only.