Wave-Function Femtometry: Hypertriton - The Ultimate Halo Nucleus

TL;DR

This paper confirms the halo structure of the hypertriton through LHC proton-proton collision measurements, providing insights into hypernuclear interactions relevant to dense nuclear matter.

Contribution

It presents the first measurement of hypertriton production at the LHC and estimates the Lambda separation distance within a coalescence model.

Findings

Hypertriton exhibits a halo-like structure confirmed by experimental data.

The Lambda separation from the deuteron core is estimated at approximately 9.54 fm.

The production yield aligns with nuclear coalescence model predictions.

Abstract

The interaction between nucleons and hyperons - baryons containing a strange quark - is key to understanding the properties of dense nuclear matter, such as that expected in the interior of neutron stars. Direct scattering experiments are hindered by the short lifetime of hyperons, prompting the study of hypernuclei - bound states of nucleons and hyperons - as an alternative approach. The lightest known hypernucleus, the hypertriton ($^3_{\Lambda}$H), is a weakly bound state composed of a proton, a neutron and a $\Lambda$ hyperon, and is believed to exhibit a halo-like structure with the $\Lambda$ being loosely bound to a deuteron core. Based on the first measurement of hypertriton production in proton-proton collisions at the CERN Large Hadron Collider (LHC), its halo structure is confirmed. A successful description of the hypertriton production yield within the nuclear coalescence framework enables an estimation of the $\Lambda$ separation from the deuteron core as $9.54^{+2.67}_{-1.11}$ fm.