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Observation of an excited $Omega^-$ baryon

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 نشر من قبل John M. Yelton
 تاريخ النشر 2018
  مجال البحث
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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 $2012.4pm0.7 {rm (stat)pm 0.6 (rm syst)} {rm MeV}/c^2$ 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.



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