2023/08/31 by Cui, Bo-Yan, Shen, Yue-Long, Wang, Chao +1
#FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph)
paper · doi:10.48550/arxiv.2308.16436
The radiative leptonic B→ γℓνℓ decay serves as an ideal platform to determine the B-meson inverse moment which is a fundamental nonperturbative parameter for the B meson. In this paper, we explore precise QCD contributions to this decay with an energetic photon. We reproduce the next-to-next-to-leading-logarithmic resummation formula for the decay amplitude at leading power in Λ\rm QCD/mb. Employing operator identities, we calculate subleading-power contributions from the expansion of the hard-collinear propagator of the internal up quark and the heavy-quark expansion of the bottom quark. We update the contributions from the hadronic structure of the photon to the \decay process with the dispersion technique. Together with other yet known power corrections, phenomenological applications including the partial branching fraction and ratio of the branching fractions of the radiative B decay are investigated.