2025/07/18 by LHCb collaboration, R. Aaij, A. S. W. Abdelmotteleb +2322 · 2 voices · 1 citation
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #hep-ex
paper · pdf · doi:10.48550/arxiv.2507.14401
arxiv published 2025/07/18 · arxiv updated 2025/12/29
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 is \frac\cal B(B0→ ρ(770)0γ)\cal B(B0→ K*(892)0γ)=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 as \calB(B0→ ρ(770)0γ) =(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.