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Decoupling of heavy quarks in HQET

A. G. Grozin·A. V. Smirnov·V. A. Smirnov
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Abstract

Decoupling of c-quark loops in b-quark HQET is considered. The decoupling coefficients for the HQET heavy-quark field and the heavy-light quark current are calculated with the three-loop accuracy. The last result can be used to improve the accuracy of extracting f_B from HQET lattice simulations (without c-quark loops). The decoupling coefficient for the flavour-nonsinglet QCD current with n antisymmetrized gamma-matrices is also obtained at three loops; the result for the tensor current (n=2) is new.

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A. G. Grozin, A. V. Smirnov, V. A. Smirnov. 2007-03-08. Decoupling of heavy quarks in HQET. https://doi.org/10.1088/1126-6708%2F2006%2F11%2F022

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