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arXiv · hep-lat/9510006

Update on Quarkonium Spectroscopy and $α_{strong}$ from NRQCD

C. T. H. Davies·K. Hornbostel·G. P. Lepage·A. J. Lidsey·P. McCallum·J. Shigemitsu·J. Sloan
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Abstract

NRQCD results for Upsilon and Charmonium using both dynamical and quenched configurations are presented. We investigate dependence on the light dynamical quark mass. Preliminary dynamical ($n_f = 2$) Charmonium data are combined with quenched results to extract the strong coupling constant $α_P^{(n_f)}$ for the physical number of light dynamical quarks, $n_f = 3$. Good agreement is found with calculations based on the Upsilon system. We show that a discrepancy in $α_P^{(n_f=0)}$, found between the Upsilon and Charmonium systems in the quenched theory, disappears upon extrapolating to the physical number of flavors. Results for the strong coupling constant $α_{\overline{MS}}$ are presented and sources of systematic error investigated.

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C. T. H. Davies, K. Hornbostel, G. P. Lepage, A. J. Lidsey, P. McCallum, J. Shigemitsu, J. Sloan. 1995-10-04. Update on Quarkonium Spectroscopy and $α_{strong}$ from NRQCD. https://arxiv.org/abs/hep-lat/9510006

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