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arXiv · hep-ph/0311125

The Evidence for a Pentaquark Signal and Kinematic Reflections

A. R. Dzierba·D. Krop·M. Swat·A. P. Szczepaniak·S. Teige
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Abstract

Several recent experiments have reported evidence for a narrow baryon resonance with positive strangeness ($Θ^+$) at a mass of 1.54 GeV/$c^2$. Baryons with $S=+1$ cannot be conventional $qqq$ states and the reports have thus generated much theoretical speculation about the nature of possible $S=+1$ baryons, including a 5-quark, or pentaquark, interpretation. We show that narrow enhancements in the $K^+n$ effective mass spectrum can be generated as kinematic reflections resulting from the decay of mesons, such as the $f_2(1275)$, the $a_2(1320)$ and the $ρ_3(1690)$.

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A. R. Dzierba, D. Krop, M. Swat, A. P. Szczepaniak, S. Teige. 2003-11-10. The Evidence for a Pentaquark Signal and Kinematic Reflections. https://doi.org/10.1103/physrevd.69.051901

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