Structure of single-$\Lambda$ hypernuclei with chiral hyperon-nucleon potentials

TL;DR

This study investigates the structure of single-$\Lambda$ hypernuclei using chiral hyperon-nucleon potentials at different orders, revealing how these interactions influence binding energies and spin-orbit splittings across a wide range of hypernuclei.

Contribution

It provides a systematic analysis of hypernuclear structure with chiral potentials at LO and NLO, comparing their effectiveness and agreement with experimental data.

Findings

LO potentials tend to overbind hypernuclei.

NLO13 underbinds most hypernuclei.

NLO19 shows good agreement with experimental data.

Abstract

The structure of single-$\Lambda$ hypernuclei is studied using the chiral hyperon-nucleon potentials derived at leading order (LO) and next-to-leading order (NLO) by the J\"{u}lich--Bonn--Munich group. Results for the separation energies of $\Lambda$ single-particle states for various hypernuclei from $^5_{\Lambda}$He to $^{209}_{\,\,\,\,\,\Lambda}$Pb are presented for the LO interaction and the 2013 (NLO13) and 2019 (NLO19) versions of the NLO potentials. It is found that the results based on the LO potential show a clear tendency for overbinding while those for the NLO13 interaction underbind most of the considered hypernuclei. A qualitatively good agreement with the data is obtained for the NLO19 interaction over a fairly large range of mass number values when considering the uncertainty due to the regulator dependence. A small spin-orbit splitting of the $p$-, $d$-, $f$-, and $g$-wave states is predicted by all interactions, in line with the rather small values observed in pertinent experiments.