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arXiv · 2212.04835

Charmonium-like states with $J^{P}=1^{+}$ and isospin 1

Mitja Sadl·Sara Collins·M. Padmanath·Sasa Prelovsek
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Abstract

Many mesons with properties incompatible with a $\bar cc$ structure have already been discovered, e.g. the $Z_c$ mesons with isospin 1. We investigate the spectrum of exotic charmonium-like mesons using lattice QCD. The focus is on $\bar cc \bar qq$ states with $J^{PC}=1^{+\pm}$ and isospin 1. This is the first study of four-quark states with these quantum numbers, a non-zero total momentum and two different lattice volumes. We extract the energy levels and determine the scattering length for $D\bar D^*$ scattering close to the threshold using L\"uscher's formalism. Our preliminary results show that the energy shifts for eigenstates dominated by $D\bar{D}^*$ are very small in the $1^{++}$ channel and consistent with zero in the $1^{+-}$ channel.

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Mitja Sadl, Sara Collins, M. Padmanath, Sasa Prelovsek. 2022-12-09. Charmonium-like states with $J^{P}=1^{+}$ and isospin 1. https://arxiv.org/abs/2212.04835

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