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arXiv · 1907.09393

Double Polarization Observables in Pentaquark Photoproduction

JPAC Collaboration·Daniel Winney·Cristiano Fanelli·Alessandro Pilloni·Astrid N. Hiller Blin·Cesar Fernandez-Ramirez·Miguel Albaladejo·Vincent Mathieu·Victor I. Mokeev·Adam P. Szczepaniak
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Abstract

We investigate the properties of the hidden charm pentaquark-like resonances first observed by LHCb in 2015, by measuring the polarization transfer KLL between the incident photon and the outgoing proton in the exclusive photoproduction of J/psi near threshold. We present a first estimate of the sensitivity of this observable to the pentaquark photocouplings and hadronic branching ratios, and extend our predictions to the case of initial state helicity correlation ALL, using a polarized target. These results serve as a benchmark for the SBS experiment at Jefferson Lab, which proposes to measure for the first time the helicity correlations ALL and KLL in J/psi exclusive photoproduction, in order to determine the pentaquark photocouplings and branching ratios.

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JPAC Collaboration, Daniel Winney, Cristiano Fanelli, Alessandro Pilloni, Astrid N. Hiller Blin, Cesar Fernandez-Ramirez, Miguel Albaladejo, Vincent Mathieu, Victor I. Mokeev, Adam P. Szczepaniak. 2019-07-22. Double Polarization Observables in Pentaquark Photoproduction. https://doi.org/10.1103/physrevd.100.034019

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