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arXiv · 1612.06490

Amplitude analysis and the nature of the Zc(3900)

JPAC Collaboration·A. Pilloni·C. Fernandez-Ramirez·A. Jackura·V. Mathieu·M. Mikhasenko·J. Nys·A. P. Szczepaniak
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Abstract

The microscopic nature of the XYZ states remains an unsettled topic. We show how a thorough amplitude analysis of the data can help constraining models of these states. Specifically, we consider the case of the Zc(3900) peak and discuss possible scenarios of a QCD state, virtual state, or a kinematical enhancement. We conclude that current data are not precise enough to distinguish between these hypotheses, however, the method we propose, when applied to the forthcoming high-statistics measurements should shed light on the nature of these exotic enhancements.

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JPAC Collaboration, A. Pilloni, C. Fernandez-Ramirez, A. Jackura, V. Mathieu, M. Mikhasenko, J. Nys, A. P. Szczepaniak. 2016-12-20. Amplitude analysis and the nature of the Zc(3900). https://doi.org/10.1016/j.physletb.2017.06.030

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