Strong decays of the hadronic molecule $\Omega^\ast (2012)$

TL;DR

This paper investigates the decay mechanisms of the excited hyperon $ ext{Omega}^*(2012)$ using a hadronic molecular model, showing that two-body decays dominate and align with experimental data, suggesting a mixed hadronic structure.

Contribution

It introduces a hadronic molecular approach to analyze $ ext{Omega}^*(2012)$ decays, highlighting the significance of mixed $ ext{Xi} ar K$ and $ ext{Omega} ext{eta}$ components in decay behavior.

Findings

Two-body decay widths are in the few MeV range.

Three-body decay rates are suppressed compared to two-body decays.

Total decay width matches experimental measurements.

Abstract

Strong two- and three-body decays of the new excited hyperon $\Omega^*(2012)$ are discussed in the hadronic molecular approach. The $\Omega^*(2012)$ state is considered to contain the mixed $\Xi \bar K$ and $\Omega \eta$ hadronic components. In our calculations we use a phenomenological hadronic Lagrangian describing the coupling of the bound states to its constituents and of the constituents to other hadrons occurring in the final state. Our results show that the decay widths of the two-body decay modes $\Omega^*(2012) \to \Xi \bar K$ lie in the few MeV region and are compatible with or dominate over the rates of the three-body modes $\Omega^*(2012) \to \Xi \pi \bar K$. The sum of two- and three-body decay widths is consistent with a width of the $\Omega^*(2012)$ originally measured by the Belle Collaboration. A possible scenario for the suppression of the three-body decay rate recently noticed by the Belle Collaboration is due to the dominant admixture of the $\Omega \eta$ hadronic component in the $\Omega^*(2012)$ state.