Evidence for the decay $B^0 \to μ^+ μ^-$ and improved measurements of the decay $B^0_s \to μ^+ μ^-$

The first single-experiment evidence for the rare decay $B^0 \to μ^+ μ^-$ and the world's most precise measurements of the $B^0_s \to μ^+ μ^-$ branching fraction and effective lifetime are reported. The results are obtained using Run 3 proton-proton collision data corresponding to an integrated lumi