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arXiv · hep-ph/9908363

Operator product expansion in static-quark effective field theory: large perturbative correction

Abstract

We calculate the coefficients of operators with dimensions d <= 7 in the operator product expansion of correlators of q Gamma Q currents, for the effective field theory of an infinite-mass quark, Q. Exact two-loop results are obtained, with an arbitrary gauge group and spacetime dimension, for the perturbative (d=0) and quark-condensate (d=3) contributions, confirming our previous result for the anomalous dimension of the current. Leading-order results are given for light-quark operators with d=5, 6, 7 and gluon operators with d=4, 6. The existence of a perturbative correction of order 100% precludes a reliable determination of f_B from non-relativistic sum rules.

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D. J. Broadhurst, A. G. Grozin. 1999-08-16. Operator product expansion in static-quark effective field theory: large perturbative correction. https://doi.org/10.1016/0370-2693(92)92009-6

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