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arXiv · 1812.05112

Distribution Amplitudes of Heavy-Light Mesons

Daniele Binosi·Lei Chang·Minghui Ding·Fei Gao·Joannis Papavassiliou·Craig D. Roberts
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Abstract

A symmetry-preserving approach to the continuum bound-state problem in quantum field theory is used to calculate the masses, leptonic decay constants and light-front distribution amplitudes of empirically accessible heavy-light mesons. The inverse moment of the $B$-meson distribution is particularly important in treatments of exclusive $B$-decays using effective field theory and the factorisation formalism; and its value is therefore computed: $\lambda_B(\zeta = 2\,{\rm GeV}) = 0.54(3)\,$GeV. As an example and in anticipation of precision measurements at new-generation $B$-factories, the branching fraction for the rare $B\to \gamma(E_\gamma) \ell \nu_\ell$ radiative decay is also calculated, retaining $1/m_B^2$ and $1/E_\gamma^2$ corrections to the differential decay width, with the result $\Gamma_{B\to \gamma \ell \nu_\ell}/\Gamma_B = 0.47(15)$ on $E_\gamma > 1.5\,$GeV.

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Daniele Binosi, Lei Chang, Minghui Ding, Fei Gao, Joannis Papavassiliou, Craig D. Roberts. 2018-12-12. Distribution Amplitudes of Heavy-Light Mesons. https://arxiv.org/abs/1812.05112

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