Search for Exotic Baryons in 800 GeV pp (rtarrow) pXiPiX
We report the results of a high-statistics, sensitive search for narrow baryon resonances decaying to $Ξ^-π^-$, $Ξ^-π^+$, $\barΞ^+π^-$, and $\barΞ^+π^+$. The only resonances observed are the well known $Ξ^0(1530)$ and $\bar{Ξ^0}(1530)$. No evidence is found for a state near 1862 MeV, previously reported by NA49\cite{NA49}. At the 95% confidence level, we find the upper limit for the production of a Gaussian enhancement with $σ=7.6$ MeV in the $Ξ^-π^-$ effective mass spectrum to be 0.3% of the number of observed $Ξ^0(1530)\toΞ^-π^+$. We find similarly restrictive upper limits for an enhancement at 1862 MeV in the $Ξ^-π^+$, $\barΞ^+π^-$, and $\barΞ^+π^+$ mass spectra.
hep-ex↗