Hyperon Pair Production at BESIII

TL;DR

This paper reports new experimental measurements of hyperon pair production and multi-body decays in electron-positron collisions at BESIII, revealing evidence for specific decay modes and providing insights into hyperon production mechanisms.

Contribution

It presents the first evidence for certain hyperon decay modes and measures cross sections across a range of energies, advancing understanding of hyperon production and charmonium decay processes.

Findings

Evidence for $ ext{psi}(3770) o ext{Lambda}ar{ extLambda}$ and $ extXi^-ar{ extXi}^+$ decays.

Measurement of Born cross sections from 3.5 to 4.9 GeV.

Observation of $ ext{psi}(4160) o K^-ar extXi^+ extLambda+c.c.$.

Abstract

This poster presents recent experimental findings from the BESIII experiment, including two categories of studies. Firstly, it reports the studies on the hyperon pair production in the processes $e^+e^- \to \Lambda\bar\Lambda$, $\Sigma^+\bar\Sigma^-$, $\Sigma^0\bar\Sigma^0$, $\Xi^0\bar\Xi^0$ and $\Xi^-\bar\Xi^+$. The Born cross sections for these processes are measured at center-of-mass energies ranging from $3.5$ to $4.9$ GeV. For the first time, evidence for the decays $\psi(3770)\to\Lambda\bar\Lambda$ and $\Xi^-\bar\Xi^+$ is found. Secondly, it reports the measurements of the Born cross sections of multi-body decays involving hyperon final states. The evidence of $\psi(4160)\to K^-\bar\Xi^+\Lambda+c.c.$ is found. These results offer new perspectives on hyperon production in $e^+e^-$ annihilation and the decay mechanism of vector charmonium(-like) states, contributing to our understanding of hadron dynamics.