Using the CLEO detector at the Cornell Electron Storage Ring, we observe $B$-meson decays to ${\Lambda }_c^{+}$ and report on improved measurements of inclusive branching fractions and momentum spectra of other baryons. For the inclusive decay $\overline{B}\to {\Lambda }_c^{+}X$ with ${\Lambda }_c^{+}\to p{K}^{-}{\pi }^{+}$, we find that the product branching fraction $B(\overline{B}\to {\Lambda }_c^{+}X)B({\Lambda }_c^{+}\to p{K}^{-}{\pi }^{+})=(0.273\mathrm{}\pm 0.051\pm 0.039)\%$. Our measured inclusive branching fractions to noncharmed baryons are $B(B\to pX)=(8.0\mathrm{}\pm 0.5\pm 0.3)\%$, $B(B\to \Lambda X)=(3.8\mathrm{}\pm 0.4\pm 0.6)\%$, and $B(B\to {\Xi }^{-}X)=(0.27\mathrm{}\pm 0.05\pm 0.04)\%$. From these rates and studies of baryon-lepton and baryon-antibaryon correlations in $B$ decays, we have estimated the branching fraction $B(\overline{B}\to {\Lambda }_c^{+}X)$ to be (6.4±0.8±0.8)%. Combining these results, we calculate $B({\Lambda }_c^{+}\to p{K}^{-}{\pi }^{+})$ to be (4.3±1.0±0.8)%.

• Received 15 April 1991

DOI:https://doi.org/10.1103/PhysRevD.45.752