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: λB(ζ=2GeV)=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→γ(Eγ)ℓνℓ radiative decay is also calculated, retaining 1/m2B and 1/E2γ corrections to the differential decay width, with the result ΓB→γℓνℓ/ΓB=0.47(15) on Eγ>1.5GeV.
Date of publication:
Phys. Lett. B 790, 257-262 (2019)