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arXiv · 1110.2381

Charmonium spectroscopy and mixing with light quark and open charm states from nF=2 lattice QCD

Gunnar S. Bali·Sara Collins·Christian Ehmann
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Abstract

We study the charmonium spectrum including higher spin and gluonic excitations. We determine an upper limit on the mixing of the eta_c ground state with light pseudoscalar flavour-singlet mesons and investigate the mixing of charmonia near open charm thresholds with pairs of (excited) D and anti-D mesons. For charm and light valence quarks and nF=2 sea quarks, we employ the non-perturbatively improved Sheikholeslami-Wohlert (clover) action. Excited states are accessed using the variational technique, starting from a basis of suitably optimised operators. For some aspects of this study, the use of improved stochastic all-to-all propagators was essential.

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Gunnar S. Bali, Sara Collins, Christian Ehmann. 2011-11-18. Charmonium spectroscopy and mixing with light quark and open charm states from nF=2 lattice QCD. https://doi.org/10.1103/physrevd.84.094506

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