mesons decaying into a lepton and a charmed meson collected in pp collisions at s= 1.8
TeV. A flavor tagging technique is employed which relies upon the correlation between the
flavor of B mesons and the charge of a nearby particle. We measure the flavor oscillation
frequency to be Δ md= 0.471− 0.068+ 0.078±0.034 ps− 1. The tagging method is also
demonstrated in exclusive samples of B u+→ J/ψ K+ and B d 0→ J/ψ K* 0 (892), where …