Observation of ${\mathit{B}}^{+}\to {\chi }_{c0\mathrm{}}{K}^{+}$

Using a sample of $31.3\times {10}^{6}B\overline{B}$ pairs collected with the Belle detector at the $\Upsilon \left(4S\right)$ resonance, we make the first observation of the charged $B$ meson decay to ${\chi }_{c0\mathrm{}}$ and a charged kaon. The measured branching fraction is $B(B^{+}\to {\chi }_{c0\mathrm{}}{K}^{+})=({6.0}_{-1.8\mathrm{}}^{+2.1\mathrm{}}\pm 1.1)\times {10}^{-4\mathrm{}}$, where the first error is statistical, and the second is systematic.