Branching fraction and effective lifetime measurements of the rare decay B0s → μ+ μ− and searches for the decays B0 → μ+ μ− and B0s → μ+ μ− γ are reported using proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV, corresponding to a luminosity of 9 fb^−1. The branching fraction B(B0s → μ+ μ−) = (3.09{−0.43}{+0.46}{−0.11}{+0.15}) × 10^−9 and the effective lifetime τ(B0s → μ+ μ−) = (2.07 ± 0.29 ± 0.03) ps are measured, where the first uncertainty is statistical and the second systematic. No significant signal for B0 → μ+ μ− and B0s → μ+ μ− γ decays is found and upper limits B(B0 → μ+ μ−) < 2.6 × 10^−10 and B(B0s → μ+ μ− γ) < 2.0 × 10^−9 at the 95% C.L. are determined, where the latter is limited to the range m_μμ > 4.9 GeV/c^2. The results are in agreement with the standard model expectations.
Analysis of Neutral B-Meson Decays into Two Muons
Calabrese, R.Membro del Collaboration Group
;Capriotti, L.Membro del Collaboration Group
;Fiorini, M.Membro del Collaboration Group
;Franzoso, E.Membro del Collaboration Group
;Giugliano, C.Membro del Collaboration Group
;Guarise, M.Membro del Collaboration Group
;Luppi, E.Membro del Collaboration Group
;Pappalardo, L. L.Membro del Collaboration Group
;Tomassetti, L.Membro del Collaboration Group
;
2022
Abstract
Branching fraction and effective lifetime measurements of the rare decay B0s → μ+ μ− and searches for the decays B0 → μ+ μ− and B0s → μ+ μ− γ are reported using proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV, corresponding to a luminosity of 9 fb^−1. The branching fraction B(B0s → μ+ μ−) = (3.09{−0.43}{+0.46}{−0.11}{+0.15}) × 10^−9 and the effective lifetime τ(B0s → μ+ μ−) = (2.07 ± 0.29 ± 0.03) ps are measured, where the first uncertainty is statistical and the second systematic. No significant signal for B0 → μ+ μ− and B0s → μ+ μ− γ decays is found and upper limits B(B0 → μ+ μ−) < 2.6 × 10^−10 and B(B0s → μ+ μ− γ) < 2.0 × 10^−9 at the 95% C.L. are determined, where the latter is limited to the range m_μμ > 4.9 GeV/c^2. The results are in agreement with the standard model expectations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.