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Mesurement of the B0 - anti-B0 Mixing Parameter Delta m_d using Semileptonic B0 Decays

Belle Collaboration·K. Hara·M. Hazumi
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Abstract

We present a measurement of the B^0-B^0bar mixing parameter Delta m_d using neutral B meson pairs in a 29.1 fb^{-1} data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e^+e^- collider. We exclusively reconstruct one neutral B meson in the semileptonic B^0 \to D^{*-}\ell^+νdecay mode and identify the flavor of the accompanying B meson from its decay products. From the distribution of the time intervals between the two flavor-tagged B meson decay points, we obtain Delta m_d = (0.494 +- 0.012 +- 0.015) ps^{-1}, where the first error is statistical and the second error is systematic.

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Belle Collaboration, K. Hara, M. Hazumi. 2002-12-22. Mesurement of the B0 - anti-B0 Mixing Parameter Delta m_d using Semileptonic B0 Decays. https://doi.org/10.1103/physrevlett.89.251803

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