6533b7dcfe1ef96bd1272ae5

RESEARCH PRODUCT

Measurement of the branching fraction forB±→χc0K±

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description

We present a measurement of the branching fraction of the decay ${B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{\ensuremath{\chi}}_{c0}{K}^{\ifmmode\pm\else\textpm\fi{}}$ from a sample of $89\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ pairs collected by the BABAR detector at the SLAC PEP-II asymmetric-energy B factory. The ${\ensuremath{\chi}}_{c0}$ meson is reconstructed through its two-body decays to ${\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ and ${K}^{+}{K}^{\ensuremath{-}}.$ We measure $\mathcal{B}{(B}^{\ifmmode\pm\else\textpm\fi{}}\stackrel{\ensuremath{\rightarrow}}{}{\ensuremath{\chi}}_{c0}{K}^{\ifmmode\pm\else\textpm\fi{}})\ifmmode\times\else\texttimes\fi{}\mathcal{B}({\ensuremath{\chi}}_{c0}\stackrel{\ensuremath{\rightarrow}}{}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}})=[{1.32}_{\ensuremath{-}0.27}^{+0.28}(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.26(\mathrm{syst})]\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$ and $\mathcal{B}{(B}^{\ifmmode\pm\else\textpm\fi{}}\stackrel{\ensuremath{\rightarrow}}{}{\ensuremath{\chi}}_{c0}{K}^{\ifmmode\pm\else\textpm\fi{}})\ifmmode\times\else\texttimes\fi{}\mathcal{B}({\ensuremath{\chi}}_{c0}\stackrel{\ensuremath{\rightarrow}}{}{K}^{+}{K}^{\ensuremath{-}})=[{1.49}_{\ensuremath{-}0.34}^{+0.36}(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.22(\mathrm{syst})]\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}.$ Using the known values for the ${\ensuremath{\chi}}_{c0}$ decays branching fractions, we combine these results to obtain $\mathcal{B}{(B}^{\ifmmode\pm\else\textpm\fi{}}\ensuremath{\rightarrow}{\ensuremath{\chi}}_{c0}{K}^{\ifmmode\pm\else\textpm\fi{}})=(2.7\ifmmode\pm\else\textpm\fi{}0.7)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}.$