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arXiv · 1410.8828

Study of the Zc+ channel in lattice QCD

Luka Leskovec·Sasa Prelovsek·C. B. Lang·Daniel Mohler
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Abstract

Several charged charmonium-like hadrons called $Z_c$ have been recently discovered by different experiments. In contrast to conventional hadrons these contain at least two valence quarks and antiquarks ($\bar{c}c\bar{d}u$). We perform a lattice QCD simulation of the $I^G(J^{PC})=1^+(1^{+-})$ channel including all relevant two-meson operators under 4.3 GeV: $J/ψπ$, $ψ_{2S}π$, $ψ_{1D}π$, $D \bar{D}^*$, $D^* \bar{D}^*$, $η_c ρ$ as well as additional diquark anti-diquark operators. In our $N_f = 2$ simulation with pion mass at 266 MeV we are able to identify all two-meson levels within the energy region of interest. However we find no additional level identifiable as a candidate for $Z_c$.

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Luka Leskovec, Sasa Prelovsek, C. B. Lang, Daniel Mohler. 2014-11-24. Study of the Zc+ channel in lattice QCD. https://arxiv.org/abs/1410.8828

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