Measurements of the branching fractions <i>B</i>(<i>B</i><SUP>-</SUP> → (Λ)over-bar<sub>c</sub><SUP>-</SUP>Ξ<sub>c</sub>′<sub>0</sub>), <i>B</i>(<i>B</i><SUP>-</SUP> → (Λ)over-bar<sub>c</sub><SUP>-</SUP>Ξ<sub>c</sub>(2645)<SUP>0</SUP>) and <i>B</i>(<i>B</i><SUP>-</SUP> → (Λ)over-bar<sub>c</sub><SUP>-</SUP>Ξ<sub>c</sub>(2790)<SUP>0</SUP>)

Abstract

Using the data sample of 711 fb(-1) of Upsilon(4S) on-resonance data taken by the Belle detector at the KEKB asymmetric-energy electron-positron collider, we present the first measurements of branching fractions of the decays B- -> (Lambda) over bar (-)(c)Xi('0)(c), B- -> (Lambda) over bar (-)(c)Xi(c)(2645)(0) , and B- -> (Lambda) over bar (-)(c)Xi(c) (2790)(0). The signal yields for these decays are extracted from the recoil mass spectrum of the system recoiling against (Lambda) over bar (- )(c)baryons in selected B(-)candidates. The branching fraction of B- -> (Lambda) over bar (-)(c)Xi(c)(2790)(0) is measured to be (1.1 +/- 0.4 +/- 0.2) x 10(-3) , where the first uncertainty is statistical and the second is systematic. The 90% credibility level upper limits on B(B- -> (Lambda) over bar (-)(c)Xi('0)(c))( )and B(B- -> (Lambda) over bar (-)(c)Xi(c)(2645)(0) are determined to be 6.5 x 10(-4) and 7.9 x 10(-4) , respectively.