Study of the $J/\psi \to \Lambda\bar{\Sigma}^0\eta$ reaction

TL;DR

This paper investigates the isospin-violating decay of J/psi into Lambda, Sigma0, and eta particles, using a theoretical model that accounts for final state interactions and SU(3) symmetry, matching experimental data.

Contribution

It introduces a novel theoretical approach considering dominant terms and final state interactions to explain the J/psi decay process involving SU(3) singlet formations.

Findings

Good agreement with experimental mass distributions

Identification of key channels as ar K N and K i

Non-cancellation of charged and neutral particle terms

Abstract

We study the isospin violating $J/\psi \to \Lambda\bar \Sigma^0 \eta $ reaction, recently measured by the BESIII collaboration, by looking at the dominant terms with $\bar \Sigma^0$ and a pair of pseudoscalar-baryon particles that form together an SU(3) singlet and can thus couple to the $J/\psi $. Next we allow these pairs to undergo final state interaction to produce the final $\eta \Lambda$. We find that the relevant original channels are $\bar K N$ and $K \Xi$, and the non cancelation of terms involving charged and neutral particles, because of their different masses, is responsible for the reaction. With that mechanism we find a good agreement with the three experimental mass distributions.