Measurement of the Bd 0-B̄d 0 flavor oscillation frequency and study of same side flavor tagging of B mesons in pp̄ collisions

B d 0 -B d 0 oscillations are observed in "self-tagged" samples of partially reconstructed B 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 Δm d =0.471 -0.068 +0.078 ±0.034 ps -1 . The tagging method is also demonstrated in exclusive samples of B u + →J/ψK + and B d 0 →J/ψK *0 (892), where similar flavor-charge correlations are observed. The tagging characteristics of the various samples are compared with each other, and with Monte Carlo simulations.