In this paper we study the semileptonic decays of B + c → D(s) (l + ν l , l + l − , νν) (here l stands for e, µ, or τ ). After evaluating the B + c → (D (s) , D * (s) ) transition form factors F 0,+,T (q 2 ) and V (q 2 ), A 0,1,2 (q 2 ), T 1,2,3 (q 2 ) by employing the perturbative QCD factorization approach, we calculate the branching ratios for all these semileptonic decays. Our predictions for the values of the B + c → D (s) and B + c → D * (s) transition form factors are consistent with those obtained by using other methods. The branching ratios of the decay modes withνν are almost an order of magnitude larger than the corresponding decays with l + l − after the summation over the three neutrino generations. The branching ratios for the decays with b → d transitions are much smaller than those decays with the b → s transitions, due to the Cabibbo-Kobayashi-Maskawa suppression. We define ratios R D and R D * for the branching ratios with the τ lepton versus µ, e lepton final states to cancel the uncertainties of the form factors, which could possibly be tested in the near future.

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Using 116.1 fb(-1) of data collected by the BABAR detector, we present an analysis of xi(c)(0) production in B decays and from the cc continuum, with the xi(c)(0) decaying into omega- K+ and xi- pi+ final states. We measure the ratio of branching fractions B(xi(c)(0) --> omega- K+)/B(xi(c)(0) --> xi- pi+) spectrum is measured on and 40 MeV below the upsilon(4S) resonance. From these spectra the branching fraction product B(B --> xi(c)(0)X) x B(xi(c)(0) --> xi- pi+) is measured to be (2.11 +/- 0.19 +/- 0.25) x 10(-4), and the cross-section product sigma(e+ e- --> xi(c)(0)X) x B(xi(c)(0) --> xi- pi+) from the continuum is measured to be (388 +/- 39 +/- 41) fb at a center-of-mass energy of 10.58 GeV.

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A measurement of the spin of the Omega(-) hyperon produced through the exclusive process Xi(c)(0)-->Omega(-)K(+) is presented using a total integrated luminosity of 116 fb(-1) recorded with the BABAR detector at the e(+)e(-) asymmetric-energy B factory at SLAC. Under the assumption that the Xi(c)(0) has spin 1/2, the angular distribution of the Lambda from Omega(-)-->LambdaK(-) decay is inconsistent with all half-integer Omega(-) spin values other than 3/2. Lower statistics data for the process Omega(c)(0)-->Omega(-)pi(+) from a 230 fb(-1) sample are also found to be consistent with Omega(-) spin 3/2. If the Xi(c)(0) spin were 3/2, an Omega(-) spin of 5/2 could not be excluded.