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The B0-B̄0 oscillation frequency δmd is measured by the LHCb experiment using a dataset corresponding to an integrated luminosity of 1.0fb-1 of proton-proton collisions at √s=7TeV, and is found to be δmd=0.5156±0.0051(stat.)±0.0033(syst.)ps-1. The measurement is based on results from analyses of the decays B0→D-π+ (D-→K+π-π-) and B0→J/ψK*0 (J/ψ→μ+μ-, K*0→K+π-) and their charge conjugated modes. © 2013 CERN.
Aaij, R., Abellan Beteta, C., Adametz, A., Adeva, B., Adinolfi, M., Adrover, C., … Zvyagin, A. (2013). Measurement of the B0-B̄0 oscillation frequency δmd with the decays B0→D-π+ and B0→J/ψK*0. Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, 719(4–5), 318–325. https://doi.org/10.1016/j.physletb.2013.01.019