Abstract
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
B(B0 → ρ(770)0γ) / 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
B(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.
B(B0 → ρ(770)0γ) / 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
B(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.
| Original language | English |
|---|---|
| Article number | 151 |
| Number of pages | 21 |
| Journal | JHEP |
| Volume | 2025 |
| Issue number | 12 |
| DOIs | |
| Publication status | Published - 19 Dec 2025 |