Measurement of the $B_d^0-\bar{B}{}_d^0$ flavor oscillation frequency and study of same side flavor tagging of B mesons in $p\bar{p}$ collisions

Abstract

$B_d^0$-$\bar{B}{}_d^0$ oscillations are observed in ``self-tagged'' samples of partially reconstructed $B$ mesons decaying into a lepton and a charmed meson collected in $p\bar{p}$ collisions at $\sqrt{s}=1.8$ TeV. A flavor tagging technique is employed which relies upon the correlation between the flavor of $B$ mesons and the charge of nearby particles. We measure the flavor oscillation frequency to be $\hat{I}”m_d=0.471_{-0.068}^{+0.078}\pm 0.034p{s}^{-1}$. The tagging method is also demonstrated in exclusive samples of $B_u^{+}\to J/\ddot{I}ˆK^{+}$ and $B_d^0\to J/\ddot{I}ˆK^{\ast 0}(892)$, where similar flavor-charge correlations are observed. The tagging characteristics of the various samples are compared with each other, and with Monte Carlo simulations.