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arXiv · 1905.04498

Two-loop evolution equation for the B-meson distribution amplitude

V. M. Braun·Yao Ji·A. N. Manashov
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Abstract

We derive the two-loop evolution equation of the B-meson light-cone distribution amplitude which is the last missing element for the next-to-next-to-leading logarithmic resummation of QCD corrections to B decays in QCD factorization. We argue that the evolution kernel to all orders in perturbation theory can be written as a logarithm of the generator of special conformal transformations times the cusp anomalous dimension, up to a scheme-dependent overall constant. Up to this constant term, the evolution kernel to a given order in perturbation theory can be obtained from the calculation of special conformal anomaly at one order less.

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V. M. Braun, Yao Ji, A. N. Manashov. 2019-05-11. Two-loop evolution equation for the B-meson distribution amplitude. https://doi.org/10.1103/physrevd.100.014023

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