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arXiv · 1804.04962

Radiative leptonic decay $B\to γ\ell ν_\ell$ with subleading power corrections

M. Beneke·V. M. Braun·Yao Ji·Yan-Bing Wei
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Abstract

We reconsider the QCD predictions for the radiative decay $B\to γ\ell ν_\ell$ with an energetic photon in the final state by taking into account the $1/E_γ, 1/m_b$ power-suppressed hard-collinear and soft corrections from higher-twist $B$-meson light-cone distribution amplitudes (LCDAs). The soft contribution is estimated through a dispersion relation and light-cone QCD sum rules. The analysis of theoretical uncertainties and the dependence of the decay form factors on the leading-twist LCDA $ϕ_+(ω)$ shows that the latter dominates. The radiative leptonic decay is therefore well suited to constrain the parameters of $ϕ_+(ω)$, including the first inverse moment, $1/λ_B$, from the expected high-statistics data of the BELLE II experiment.

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M. Beneke, V. M. Braun, Yao Ji, Yan-Bing Wei. 2018-04-13. Radiative leptonic decay $B\to γ\ell ν_\ell$ with subleading power corrections. https://doi.org/10.1007/jhep07(2018)154

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