Study of B[Over ¯]→Ξ_{C}Λ[Over ¯]_{C}^{-} and B[Over ¯]→Λ_{C}^{+}Λ[Over ¯]_{C}^{-}K[Over ¯] Decays At Babar

We report measurements of B-meson decays into two- and three-body final states containing two charmed baryons using a sample of 230x10(6) Upsilon(4S)-> B (B) over bar decays. We find significant signals in two modes, measuring branching fractions B(B-->Lambda(+)(c)(Lambda) over bar K--(c)-)=(1.14 +/- 0.15 +/- 0.17 +/- 0.60)x10(-3) and B(B-->Xi(0)(c)(Lambda) over bar (-)(c))xB(Xi(0)(c)->Xi(-)pi(+))=(2.08 +/- 0.65 +/- 0.29 +/- 0.54)x10(-5), where the uncertainties are statistical, systematic, and from the branching fraction B(Lambda(+)(c)-> pK(-)pi(+)), respectively. We also set upper limits at the 90% confidence level on two other modes: B((B) over bar (0)->Xi(+)(c)(Lambda) over bar (-)(c))xB(Xi(+)(c)->Xi(-)pi(+)pi(+))<5.6x10(-5) and B((B) over bar (0)->Lambda(+)(c)(Lambda) over bar (-)(c)(K) over bar (0))<1.5x10(-3). We observe structure centered at an invariant mass of 2.93 GeV/c(2) in the Lambda K-+(c)- mass distribution of the decay B-->Lambda(+)(c)(Lambda) over bar K--(c)-.