Understanding of the BESIII measurement of (anti)hyperon-nucleon scattering

TL;DR

This paper analyzes BESIII's recent measurements of hyperon-nucleon scattering, explaining differences in cross sections through channel contributions and examining forward angle enhancements to understand the underlying scattering mechanisms.

Contribution

It provides a dynamical interpretation of BESIII's hyperon-nucleon scattering data, highlighting the role of channel contributions and forward angle effects.

Findings

The u-channel contribution is forbidden in ar;mbda p scattering but allowed in mbda p scattering.

Forward angle enhancement in ar;mbda p differential cross section is due to t-channel effects.

The work tests the scattering mechanisms in hyperon-nucleon interactions.

Abstract

Focusing on the recent measurements of the scattering processes $\bar{\Lambda} p \rightarrow \bar{\Lambda} p$ and $\Lambda p \rightarrow \Lambda p$ reported by BESIII, we offer a dynamical interpretation of the differences in the measured total and differential cross sections for both processes. This discrepancy arises because the $u$-channel contribution is forbidden for $\bar{\Lambda} p \rightarrow \bar{\Lambda} p$ but allowed for $\Lambda p \rightarrow \Lambda p$. Additionally, we examine the enhancement effect in the forward angle region of the differential cross section for $\bar{\Lambda} p$ elastic scattering, attributed to the $t$-channel contribution. This work serves as a test to the scattering mechanism involved in these reactions.