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arXiv · 1012.2967

An alternative explanation for the $Θ(1540)$ pentaquark peak

A. Martínez Torres·E. Oset
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Abstract

We have studied the $γd \to K^+ K^- n p$ reaction in which the LEPS collaboration found a signal in the $K^+ n$ invariant mass for the claimed $Θ(1540)$ pentaquark peak. Our study reveal that the procedure used at LEPS to reconstruct the $K^+n$ invariant mass generates an artificial strength in the $Θ(1540)$ region and that the LEPS collaboration underestimated the background in that region, such that the signal observed for the $Θ(1540)$ is compatible with a fluctuation of $2σ$ over the calculated background.

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A. Martínez Torres, E. Oset. 2010-12-14. An alternative explanation for the $Θ(1540)$ pentaquark peak. https://doi.org/10.1063/1.3542013

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