Measurement of baryon production in B-meson decay

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