Search for the decays B⁺_(c) → μ⁺ ν_μγ

2026/07/14 by LHCb collaboration, R. Aaij, M. Abdelfatah +1128 · 2 voices
#hep-ex

paper · pdf

Abstract

A search for the radiative leptonic decays B⁺→μ⁺ν_μγ and B⁺_c→μ⁺ν_μγ is performed using proton-proton collision data collected with the LHCb experiment at a center-of-mass energy of 13~\rm TeV, corresponding to an integrated luminosity of 5.4~\rm fb^-1. No evidence for an excess of events over background is observed for either signal decay. Upper limits at 90% confidence level are set on the branching fractions: \calB(B⁺→μ⁺ν_μγ)_E_γ^∗ > 1 \rmGeV < 4.0 × 10^-6,
\calB(B_c⁺→μ⁺ν_μγ)_E_γ^∗ > 1 \rmGeV < 1.6 × 10^-3, where the photon energy in the B-meson rest frame, E_γ^∗, is required to be greater than 1~\rm GeV. This constitutes the first search for these decays at a hadron collider and the first experimental investigation of the B_c⁺→μ⁺ν_μγ decay to date.

Citations

• Determination of B-meson distribution amplitudes from B→ π,K,D transition form factors
• Incorporating Nuisance Parameters in Likelihoods for Multisource Spectra
• Presentation of search results: theCLstechnique

Discussions

• Search for the decays B(c)⁺→μ⁺νγ - No evidence for an excess of events over background is observed for either signal decay. This constitutes the first search for these decays at a hadron collider and [bsky, 6 points, 0 comments]
• #LHCbpaper: Search for the decays B⁺_(c) → μ⁺ ν_μγ (arXiv:2607.12825) https://arxiv.org/abs/2607.12825 [bsky, 1 points, 0 comments]

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