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First evidence for the annihilation decay mode $B^{+} to D_{s}^{+} phi$

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 نشر من قبل Sam Hall
 تاريخ النشر 2012
  مجال البحث
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Evidence for the hadronic annihilation decay mode $B^{+} to D_s^{+}phi$ is found with greater than $3sigma$ significance. The branching fraction and CP asymmetry are measured to be mathcal{B}(B^{+} to D_s^{+}phi) &=& (1.87^{+1.25}_{-0.73}({rm stat}) pm 0.19 ({rm syst}) pm 0.32 ({rm norm})) times 10^{-6}, mathcal{A}_{CP}(B^{+} to D_s^{+}phi) &=& -0.01 pm 0.41 ({rm stat}) pm 0.03 ({rm syst}). The last uncertainty on $mathcal{B}(B^{+} to D_s^{+}phi)$ is from the branching fractions of the $B^+ to D_s^+ kern 0.2embar{kern -0.2em D}{}^0$ normalization mode and intermediate resonance decays. Upper limits are also set for the branching fractions of the related decay modes $B^{+}_{(c)} to D^{+}_{(s)} K^{*0}$, $B^{+}_{(c)} to D^{+}_{(s)} kern 0.2embar{kern -0.2em K}{}^{*0}$ and ${B_c^{+} to D^{+}_{s}phi}$, including the result ${mathcal{B}(B^+ to D^+ K^{*0})} < 1.8 times 10^{-6}$ at the 90% credibility level.



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