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arXiv · hep-ph/9702341

Perturbative Corrections to a Sum Rule for the Heavy Quark Kinetic Energy

Hooman Davoudiasl·Adam K. Leibovich
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Abstract

We calculate the perturbative corrections to order α_s^2β_0 to the sum rule derived from the second moment of the time-ordered product of b \to c currents near zero recoil. This sum rule yields a bound on λ_1, the expectation value of the b quark kinetic energy operator inside the B meson. The perturbative corrections significantly weaken the bound relative to the tree level result, yielding λ_1 < -0.15 GeV^2.

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Hooman Davoudiasl, Adam K. Leibovich. 1997-02-14. Perturbative Corrections to a Sum Rule for the Heavy Quark Kinetic Energy. https://doi.org/10.1016/s0370-2693(97)00539-x

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