Effects of the two-body and three-body hyperon-nucleon interactions in \Lambda-hypernuclei

TL;DR

This study uses advanced Monte Carlo methods to evaluate the impact of two- and three-body hyperon-nucleon interactions on hypernuclei binding energies, highlighting the importance of three-body forces for accurate modeling.

Contribution

First application of auxiliary field diffusion Monte Carlo to calculate Lambda-binding energies across a wide mass range, emphasizing the role of three-body hyperon-nucleon interactions.

Findings

Three-body forces lead to binding energies close to experimental data.

Two-body forces alone produce unphysical binding energy limits.

Three-body hyperon-nucleon-nucleon force is essential for realistic hypernuclei modeling.

Abstract

Background: The calculation of the hyperon binding energy in hypernuclei is crucial to understanding the interaction between hyperons and nucleons. Purpose: We assess the relative importance of two- and three-body hyperon-nucleon force by studying the effect of the hyperon-nucleon-nucleon interaction in closed shell \Lambda-hypernuclei from A=5 to 91. Methods: The \Lambda-binding energy has been calculated using the auxiliary field diffusion Monte Carlo method for the first time, to study light and heavy hypernuclei within the same model. Results: Our results show that including a three-body component in the hyperon-nucleon interaction leads to a saturation of the \Lambda-binding energy remarkably close to the experimental data. In contrast, the two-body force alone gives an unphysical limit for the binding energy. Conclusions: The repulsive contribution of the three-body hyperon-nucleon-nucleon force is essential to reproduce, even qualitatively, the binding energy of the hypernuclei in the mass range considered.