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arXiv · 1602.03951

Search for Pentaquark Theta+ in Hadronic Reaction at J-PARC

M. Naruki
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Abstract

A variety of nuclear and hadron physics experiments are being performed using meson beams at the J-PARC Hadron Facility. As the first experiment at the facility, the pentaquark Theta+ was searched for in the pi- p -> K- X reaction with a missing-mass resolution of 2 MeV (FWHM). The number of accumulated beam pions are 7.8x10^10 and 8.1x10^10 for different beam momenta of 1.92 and 2.01 GeV/c, respectively. No significant structure was observed in the missing mass spectra. Upper limits of the production cross section are obtained to be 0.28ub/sr in the laboratory frame at 90% confidence level for each beam momenta. With a help of theoretical models, an upper limit of the total decay width of Theta+ was estimated to be 0.36 and 1.9 MeV for J^P = 1/2+ and 1/2- states, respectively.

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M. Naruki. 2016-02-12. Search for Pentaquark Theta+ in Hadronic Reaction at J-PARC. https://doi.org/10.5506/aphyspolb.47.385

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