Observation of an excited $\Omega^-$ baryon

TL;DR

This paper reports the observation of a new excited $ ext{Ω}^-$ hyperon state with specific decay modes, mass, and width, using data from the Belle detector in various Υ decays.

Contribution

First observation of an excited $ ext{Ω}^-$ hyperon with measured properties and decay channels, expanding knowledge of hyperon spectroscopy.

Findings

Observed a new excited $ ext{Ω}^-$ hyperon at 2012.4 MeV/c^2

Measured the hyperon's width as approximately 6.4 MeV

Detected the hyperon primarily in Υ(1S), Υ(2S), and Υ(3S) decays

Abstract

Using data recorded with the Belle detector, we observe a new excited hyperon, an $\Omega^{*-}$ candidate decaying into $\Xi^0K^-$ and $\Xi^-K^0_S$ with a mass of $2012.4\pm0.7\ {\rm (stat)\pm\ 0.6\ (\rm syst)}\ {\rm MeV}/c^2$ and a width of $\Gamma=6.4^{+2.5}_{-2.0}\ {\rm(stat)}\pm1.6\ {\rm(syst)}\ {\rm MeV}$. The $\Omega^{*-}$ is seen primarily in $\Upsilon(1S), \Upsilon(2S)$, and $\Upsilon(3S)$ decays.