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arXiv · 1610.01073

Excited and exotic charmonium, $D_s$ and $D$ meson spectra for two light quark masses from lattice QCD

Gavin K. C. Cheung·Cian O'Hara·Graham Moir·Michael Peardon·Sinéad M. Ryan·Christopher E. Thomas·David Tims
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Abstract

We present highly-excited charmonium, $D_s$ and $D$ meson spectra from dynamical lattice QCD calculations with light quarks corresponding to $M_{\pi} \sim 240$ MeV and compare these to previous results with $M_{\pi} \sim 400$ MeV. Utilising the distillation framework, large bases of carefully constructed interpolating operators and a variational procedure, we extract and reliably identify the continuum spin of an extensive set of excited mesons. These include states with exotic quantum numbers which, along with a number with non-exotic quantum numbers, we identify as having excited gluonic degrees of freedom and interpret as hybrid mesons. Comparing the spectra at the two different $M_\pi$, we find only a mild light-quark mass dependence and no change in the overall pattern of states.

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Gavin K. C. Cheung, Cian O'Hara, Graham Moir, Michael Peardon, Sinéad M. Ryan, Christopher E. Thomas, David Tims. 2016-10-04. Excited and exotic charmonium, $D_s$ and $D$ meson spectra for two light quark masses from lattice QCD. https://doi.org/10.1007/jhep12(2016)089

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