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Search for the Theta+ pentaquark in the gamma d -> Lambda n K+ reaction measured with CLAS

Clas Collaboration·S. Niccolai
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Abstract

For the first time, the reaction gamma d -> Lambda n K+ has been analyzed in order to search for the exotic pentaquark baryon Theta+(1540). The data were taken at Jefferson Lab, using the Hall-B tagged-photon beam of energy between 0.8 and 3.6 GeV and the CEBAF Large Acceptance Spectrometer (CLAS). No statistically significant structures were observed in the nK+ invariant mass distribution. The upper limit on the gamma d -> Lambda Theta+ integrated cross section has been calculated and found to be between 5 and 25 nb, depending on the production model assumed. The upper limit on the differential cross section is also reported.

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Clas Collaboration, S. Niccolai. 2006-04-26. Search for the Theta+ pentaquark in the gamma d -> Lambda n K+ reaction measured with CLAS. https://doi.org/10.1103/physrevlett.97.032001

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