Three-particle contributions to the renormalisation of B-meson light-cone distribution amplitudes

Abstract

We study light-cone distribution amplitudes of heavy-light systems, such as a B-meson. By an explicit computation, we determine how two-parton distribution amplitudes mix with three-parton ones at one loop: ϕ_+ is shown to mix only into itself, whereas ϕ_- mixes with the difference of three-parton distribution amplitudes Ψ_A-Ψ_V. We determine the corresponding anomalous dimension and we check the gauge independence of our result by considering a general covariant gauge. Finally, we comment on some implications of our result for phenomenological models of these distribution amplitudes.

21 pages, 5 figures, some comments and 2 references added, except for typesetting matches version published in JHEP