K$^-$ multi-nucleon absorption cross sections and branching ratios in $\Lambda$p and $\Sigma^0$p final states

TL;DR

This study measures low-energy K$^-$ multi-nucleon absorption cross sections and branching ratios in $ ext{Lambda}p$ and $ ext{Sigma}^0p$ final states using experimental data from the AMADEUS collaboration, providing insights into absorption processes.

Contribution

It provides the first experimental determination of K$^-$ multi-nucleon absorption cross sections and branching ratios at low energies, including analysis of potential bound state contributions.

Findings

Measured K$^-$ absorption cross sections and branching ratios.

Disentangled two- and three-nucleon absorption processes.

Identified overlap of K$^-$pp bound state signals with two-nucleon absorption.

Abstract

The determination of low-energy cross sections and branching ratios of the K$^-$ multi-nucleon absorption processes in $\Lambda$p and $\Sigma^0$p final states performed by the AMADEUS collaboration is presented. Low momentum K$^-$ ($p_\mathrm{K} \simeq$ 127 MeV/c) produced at the DA$\Phi$NE collider are impinged on a Carbon target within the KLOE detector and the two and three nucleon absorption processes are disentangled by comparing the experimental data to phenomenological calculations. The $\Lambda$p spectra are interpreted in terms of K$^-$ multi-nucleon absorption processes; the possible contribution of a K$^-$pp bound state is demonstrated to overlap with the two nucleon capture process, its absolute yield thus resulting indistinguishable.