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We present an analysis of the semi-inclusive decays $B_s to D_s^- X ell^+ u$ and $B_s to D_s^{*-} X ell^+ u$, where $X$ denotes a final state that may consist of additional hadrons or photons and $ell$ is an electron or muon. The studied $B_s$ decays are contained in the $121.4~{rm fb}^{-1}$ $Upsilon(5S)$ data sample collected by the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. The branching fractions of the decays are measured to be $mathcal{B}(B_s to D_s^- X ell^+ u) = [8.2 pm 0.2 (text{stat}) pm 0.6 (text{syst}) pm 1.4 (text{ext})]%$ and $mathcal{B}(B_s to D_s^{*-} X ell^+ u) = [5.4 pm 0.4 (text{stat}) pm 0.4 (text{syst}) pm 0.9 (text{ext})]%$, where the first two uncertainties are statistical and systematic and the last is due to external parameters. The measurement also provides an estimate of the $B_s^{(*)}bar{B}_s^{(*)}$ production cross-section, $sigma(e^+e^- to B_s^{(*)}bar{B}_s^{(*)}) = (53.8 pm 1.4 (text{stat}) pm 4.0 (text{syst}) pm 3.4 (text{ext})),{rm pb}$, at the center-of-mass energy $sqrt{s} = 10.86,{rm GeV}$.
We report recent results obtained with the Belle detector using a 23.6 fb^{-1} data sample collected on the Y(5S) resonance at the KEKB asymmetric energy e^+ e^- collider. Inclusive semileptonic B_s^0 -> X^+ l^- u decays are studied for the first ti
Recent results obtained using the data sample of 23.6 fb^-1 collected on the Y(5S) resonance with the Belle detector at the KEKB asymmetric energy e+ e- collider are discussed. Measurements of several B_s^0 decay branching fractions are reported. Stu
We report a measurement of the inclusive semileptonic $B_s^0$ branching fraction in a $121~fb^{-1}$ data sample collected near the $Upsilon(5S)$ resonance with the Belle detector at the KEKB asymmetric energy $e^+ e^-$ collider. Events containing $B_
A search for mixing in the neutral D meson system has been performed using semileptonic D0 -> K(*)- e+ u and D0 -> K(*)- mu+ u decays. Neutral D mesons from D*+ -> D0 pi_s^+ decays are used and the flavor at production is tagged by the charge of th
The $b rightarrow s gamma$, $b rightarrow d gamma$ and $b rightarrow s ell^+ ell^-$ processes are allowed at higher order via the electroweak loop or box diagrams in the Standard model. It is sensitive probe to search for new physics beyond the Stand