Role of $\Xi(1690)$ in the $J/\psi\to\Xi^0\bar{\Lambda}K^0$ reaction

TL;DR

This paper investigates the role of the $ ext{Xi}(1690)$ resonance in the $J/\psi o ext{Xi}^0 ar{ ext{Lambda}} K^0$ reaction, showing it significantly influences invariant mass distributions and emphasizing its importance overlooked in prior experimental analysis.

Contribution

The study introduces a chiral unitary approach to dynamically generate the $ ext{Xi}(1690)$ resonance and demonstrates its crucial impact on reaction observables, providing a refined theoretical understanding.

Findings

The $ ext{Xi}(1690)$ resonance significantly affects invariant mass distributions.

The model accurately describes experimental invariant mass spectra.

The $ ext{Xi}(1690)$ plays a crucial role, contrary to previous neglect.

Abstract

Motivated by the recent BESIII measurements of the $J/\psi \to \Xi^0 \bar{\Lambda}K_S^0 + c.c.$ process, we investigate this reaction by considering the contributions from the $\Xi(1690)$ and $\Lambda(1890)$ resonances. The $\Xi(1690)$ state is dynamically generated from the $S$-wave pseudoscalar meson-octet baryon interactions within the chiral unitary approach. Our theoretical model provides a good description of the $\bar{\Lambda}K^0$, $\Xi^0 K^0$, and $\bar{\Lambda}\Xi^0$ invariant mass distributions. The results indicate that the $\Xi(1690)$ resonance, which was neglected in the experimental analysis by BESIII, plays a crucial role in this process. Furthermore, we evaluate the theoretical uncertainties of our model using the parametric bootstrap method. Future high-precision measurements of this process will further help to elucidate the properties of the $\Xi(1690)$ and $\Lambda(1890)$ states.