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arXiv · hep-lat/9812007

$O(aα_s)$ matching coefficients for the $ΔB$=2 operators in the lattice static theory

K-I. Ishikawa·T. Onogi·N. Yamada
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Abstract

We present the perturbative matching coefficient to $O(aα_s)$ which relates the $ΔB$=2 operator in the continuum to that of the lattice static theory, which is important in the accurate extraction of the continuum value of the $B_B$ from lattice simulations. The coefficients are obtained by the one-loop calculations in both of the continuum and lattice theory. We find that two new dimension seven operators appear at the $O(aα_s)$ with the O(1) coefficients. We also discuss the possible cancellation of $O(aα_s)$ correction in the ratio $B_B=<\bar{B}|\Op_L|B>/ ((8/3)(f_{B}M_{B})^2)$ qualitatively.

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K-I. Ishikawa, T. Onogi, N. Yamada. 1998-12-15. $O(aα_s)$ matching coefficients for the $ΔB$=2 operators in the lattice static theory. https://doi.org/10.1103/physrevd.60.034501

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