Evidence for Two Excited $ {\mathrm{\Omega }}^{-}$ Hyperons

Using $ {e}^{+}{e}^{-}$ collision data corresponding to an integrated luminosity of $ 19\text{}\text{}{\mathrm{fb}}^{-1}$ collected by the BESIII detector at center-of-mass energies ranging from 4.13 to 4.70 GeV, we report the first evidence for a new excited $ {\mathrm{\Omega }}^{-}$ hyperon, the $ \mathrm{\Omega }(2109{)}^{-}$, through the process $ {e}^{+}{e}^{-}\to \mathrm{\Omega }(2109{)}^{-}{\overline{\mathrm{\Omega }}}^{+}+\mathrm{c}.\text{}\text{}\mathrm{c}.$ with a significance of $ 4.1\sigma $. The mass and width of $ \mathrm{\Omega }(2109{)}^{-}$ are measured to be $ 2108.5\pm {5.2}_{\mathrm{stat}}\pm {0.9}_{\mathrm{syst}}\text{}\text{}\mathrm{MeV}/{c}^{2}$ and $ 18.3\pm {16.4}_{\mathrm{stat}}\pm {5.7}_{\mathrm{syst}}\text{}\text{}\mathrm{MeV}$, respectively. We also present evidence for a new production mechanism for the previously identified $ \mathrm{\Omega }(2012{)}^{-}$ via the process $ {e}^{+}{e}^{-}\to \mathrm{\Omega }(2012{)}^{-}{\overline{\mathrm{\Omega }}}^{+}+\mathrm{c}.\text{}\text{}\mathrm{c}.$ with a significance of $ 3.5\sigma $.