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arXiv · 1308.2097

Search for Z_c^+(3900) in the 1^+- channel on the lattice

Sasa Prelovsek·Luka Leskovec
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Abstract

Recently three experiments reported a discovery of manifestly exotic Z_c^+(3900) in the decay to J/psi pi+, while J and P are experimentally unknown. We search for this state on the lattice by simulating the channel with J^PC=1^+- and I=1, and we do not find a candidate for Z_c^+(3900). Instead, we only find discrete scattering states D D* and J/psi pi, which inevitably have to be present in a dynamical QCD. The possible reasons for not finding $Z_c^+$ may be that its quantum numbers are not $1^{+-}$ or that the employed interpolating fields are not diverse enough. Simulations with additional types of interpolators will be needed to reach a more definite conclusion.

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Sasa Prelovsek, Luka Leskovec. 2013-10-16. Search for Z_c^+(3900) in the 1^+- channel on the lattice. https://doi.org/10.1016/j.physletb.2013.10.009

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