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arXiv · hep-ex/0403020

Search for Theta^+ and Xi^{--}_{3/2} pentaquarks in HERA-B

K. T. Knoepfle·M. Zavertyaev·T. Zivko
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Abstract

A search for Theta^+(1540) and Xi^{--}_{3/2}(1862) pentaquark candidates has been performed in proton-induced reactions on C, Ti and W targets at sqrt(s) = 41.6 GeV studying the pK_s resp. Xi^-pi^- and Xi^-pi^+ (and charge conjugated) decay channels at mid-rapidity. With sensitivities of (Br)x(dsigma/dx_F) < 5 to 25 microbarn/nucleon, we find no evidence for narrow pentaquark peaks in any of the studied final states. Preliminary values for the upper limit of relative yield ratios at mid-rapidity are (Theta^+(1540)) / (Lambda(1520)) < 0.02, (Br)x(Xi^{--}_{3/2}(1862)) / (Xi(1530)^0) < 0.077, and (Br)x(Xi_bar^{++}_{3/2}(1862)) / (Xi_bar(1530)^0) < 0.058 at 95% CL.

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K. T. Knoepfle, M. Zavertyaev, T. Zivko. 2004-03-12. Search for Theta^+ and Xi^{--}_{3/2} pentaquarks in HERA-B. https://doi.org/10.1088/0954-3899%2F30%2F8%2F128

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