Pentaquark Search at Hermes ∗
نویسنده
چکیده
Evidence for a narrow baryon state at 1528 ± 2.6(stat) ± 2.1(syst) MeV is presented in quasi-real photoproduction on a deuterium target through the decay channel pK 0 S → pπ + π −. The statistical significance of the peak in the pK 0 S invariant mass spectrum is 4 standard deviations and its extracted intrinsic width Γ = 17 ± 9(stat)±3(syst) MeV. This state may be interpreted as the predicted S=+1 exotic Θ + (uudd¯ s) pentaquark baryon.
منابع مشابه
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