Measurement of the B0 lifetime and flavor-oscillation frequency using hadronic decays reconstructed in 2019-2021 Belle II data

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2023-05-15, 2023-05-15

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American Physical Society


We measure the B0 lifetime and flavor-oscillation frequency using B0→D(∗)-π+ decays collected by the Belle II experiment in asymmetric-energy e+e- collisions produced by the SuperKEKB collider operating at the ϒ(4S) resonance. We fit the decay-time distribution of signal decays, where the initial flavor is determined by identifying the flavor of the other B meson in the event. The results, based on 33000 signal decays reconstructed in a data sample corresponding to 190 fb-1, are τB0=(1.499±0.013±0.008) ps, Δmd=(0.516±0.008±0.005) ps-1, where the first uncertainties are statistical and the second are systematic. These results are consistent with the world-average values.



Science & Technology, Physical Sciences, Astronomy & Astrophysics, Physics, Particles & Fields, Physics, 5106 Nuclear and Plasma Physics, 5107 Particle and High Energy Physics, 4902 Mathematical Physics, 49 Mathematical Sciences, 51 Physical Sciences