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arXiv · hep-lat/9802024

Scaling of the Upsilon Spectrum in Lattice NRQCD

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

We present results for the spectrum of b-bbar bound states in the quenched approximation for three different values of the lattice spacing, in the range 0.05fm to 0.15fm. We find our results for spin-independent splittings in physical units to be independent of the lattice spacing, indicating the absence of systematic errors from discretisation effects. Spin-dependent splittings are more sensitive to the lattice spacing and higher order corrections to the action; we discuss the size of these effects and what can be done to arrive at a physical result.

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C. T. H. Davies, K. Hornbostel, G. P. Lepage, A. Lidsey, P. McCallum, J. Shigemitsu, J. Sloan. 1998-07-29. Scaling of the Upsilon Spectrum in Lattice NRQCD. https://doi.org/10.1103/physrevd.58.054505

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