Search for Pentaquarks in Proton-Nucleus Collisions with HERA-B
نویسنده
چکیده
We report on search for Θ + (1540) and Ξ 3/2 (1860) pentaquark candidates in proton-induced reactions on various nuclear targets at √ s=41.6 GeV/c 2. The analyzed data sample consists of 200 million minimum bias events recorded at HERA-B which is a fixed target experiment having acceptance at mid-rapidity. No evidence for narrow (σ ≈ 5 MeV/c 2) signals in Θ + → pK 0 S and Ξ 3/2 → Ξπ channels is observed. We present upper limits for the inclusive production of pen-taquark candidates as well as upper limits for particle ratios such as Θ + /Λ(1520) and Ξ −− /Ξ 0 .
منابع مشابه
Search for Pentaquarks with HERA-B ∗
A large data set of proton-nucleus collisions at √ s =41.6 GeV has been searched for Θ + and Ξ(1862) pentaquark candidates. In 2 · 10 8 inelas-tic events we find no evidence for narrow signals (σ ≈5 MeV/c 2) in the Θ + → pK 0 s and Ξ(1862) → Ξπ channels. Upper limits on production cross sections at mid-rapidity and on ratios of production cross sections to those of well established resonances a...
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