Study of B-0 -> D*(-) pi(+)pi(-)pi(+) and B-0 -> D*K--(+)pi(-)pi(+) decays

Using proton-proton collision data collected by the LHCb experiment at root s = 7 TeV, corresponding to an integrated luminosity of 1.0 fb(-1), the ratio of branching fractions of the B-0 -> D*(-)pi(+)pi(-)pi(+) decay relative to the B-0 -> D*(-)pi(+) decay is measured to be B(B-0 -> D*(-)pi(+)pi(-)pi(+))/B(B-0 -> D*(-)pi(+)) = 2.64 +/- 0.4(stat) +/- 0.13(syst). The Cabibbo-suppressed decay B-0 -> DK--(+)pi(-)pi(+) is observed for the first time, and the measured ratio of branching fractions is B(B-0 -> DK--(+)pi(-)pi(+))/B(B-0 -> DK--(+)pi(-)pi(+)) = (6.47 +/- 0.37(stat) +/- 0.35(syst)) x 10(-2). A search for orbital excitations of charm mesons contributing to the B-0 -> D(-)pi(+)pi(-)pi(+) final state is also performed, and the first observation of the B-0 -> (D) over bar (1)(2420)(0)pi(+)pi(-) decay is reported with the ratio of branching fractions B(B-0 ->(D-1(2420)(0)-> D*(-)pi(+))pi(-)pi(+))/B(B-0 -> D*(-)pi(+)pi(-)pi(+)) = (2.04 +/- 0.42(stat) +/- 0.22(syst)) x 10(-2), where the numerator represents a product of the branching fractions B(B-0 -> (D) over bar (1)(2420)(0)pi(-)pi(+)) and B(D-1(2420)(0) -> D*(-)pi(+)).