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

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.

Comments: 10 pages, 6 figures