B CP-Violation, Mixing and Lifetime Results from Belle

Abstract

Recent results on the $B$ CP-violation parameter $\sin 2{\varphi }_1$, the $B_d^0$-${\overline{B}}_d^0$ mixing parameter $\Delta m_d$ and $B$-meson lifetimes are reported. The results are based on 10.5 $f{b}^{-1}$ of data collected with the Belle detector at KEKB. Using both semileptonic and hadronic decay modes the neutral and charged $B$-meson lifetimes are measured to be $\taubz=1.548\pm0.035 (\mathrm{stat.})$~ps and $\taubm=1.656\pm0.038 (\mathrm{stat.})$~ps. The oscillation frequency $\Delta m_d$ for $B_d^0$-${\overline{B}}_d^0$ mixing is measured to be $0.522\pm 0.026(stat.)$~ps${}^{-1}$ using semileptonic modes and $0.527\pm 0.032(stat.)$~ps${}^{-1}$ using hadronic modes. The above results are preliminary. The time evolution of $B_d^0$ decays into $J/\psi K_S^0$, $\psi (2S)K_S^0$, ${\chi }_{c1}{K}_S^0$, ${\eta }_c{K}_S^0$, $J/\psi K_L^0$ and $J/\psi {\pi }^0$ modes are studied to obtain $\sin 2{\varphi }_1$. Using 282 fully reconstructed events, $\sin 2{\varphi }_1$ is measured to be $$\sin 2{\varphi }_1=0.58_{-0.34}^{+0.32}(stat.{)}_{-0.10}^{+0.09}(syst.).$$

5 pages, 3 figues. Proceedings for XXXVIth Rencontres de Moriond session devoted to QCD and High Energy Hadronic Interactions