Measurement of the B 0 → ρ (770) 0 γ branching fraction

Journal article

The ratio between the branching fractions of the B0 → ρ(770)0γ and B0 → K*(892)0γ decays is measured with proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of 9 fb−1. The measured value isBB0→ρ7700γBB0→K∗8920γ=0.0189±0.0007±0.0005, where the first uncertainty is statistical and the second systematic. The branching fraction for B0→ ρ(770)0γ decays is hence obtained asBB0→ρ7700γ=7.9±0.3±0.2±0.2×10−7, where the last uncertainty is due to the branching fraction of the normalisation mode. This result assumes that both the ρ(770)0 and K*(892)0 decays saturate the dihadron mass spectra considered in the analysis. It is consistent with the current world-average value and by far the most precise measurement to date.

Authors: Aaij, R; Abdelmotteleb, ASW; Abellan Beteta, C; Abudinén, F; Ackernley, T

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Springer
• Journal: Journal of High Energy Physics
• Volume: 2025
• Issue: 12
• Article number: 151
• Publication date: 2025-12-19
• Acceptance date: 2025-11-19
• DOI: 10.1007/jhep12(2025)151
• EISSN: 1029-8479
• ISSN: 1126-6708
• Language: English
• Keywords: Hadron-Hadron Scattering; B Physics; Flavour Physics; Rare Decay