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arXiv · hep-lat/9710025

Lattice HQET Calculation of the Isgur-Wise Function

Joseph Christensen·Terrence Draper·Craig McNeile
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Abstract

We calculate the Isgur-Wise function on the lattice, simulating the light quark with the Wilson action and the heavy quark with a direct lattice implementation of the heavy-quark effective theory. Improved smearing functions produced by a variational technique, MOST, are used to reduce the statistical errors and to minimize excited-state contamination of the ground-state signal. Calculating the required matching factors, we obtain $ξ'(1)=-0.64(13)$ for the slope of the Isgur-Wise function in continuum-HQET in the $\barMS$ scheme at a scale of $4.0 $GeV.

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Joseph Christensen, Terrence Draper, Craig McNeile. 1997-10-06. Lattice HQET Calculation of the Isgur-Wise Function. https://doi.org/10.1016/s0920-5632(97)00775-5

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