Observation of Λ0b → D+pπ−π− and Λ0b → D*+pπ−π− decays

The multihadron decays Λ0b → D+pπ−π− and Λ0b → D*+pπ−π− are observed in data corresponding to an integrated luminosity of 3 fb−1, collected in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV by the LHCb detector. Using the decay Λ0b → Λ+cπ+π−π− as a normalisation channel, the ratio of branching fractions is measured to be B(Λ0b→D+pπ−π−)B(Λ0b→Λ0cπ+π−π−)×B(D+→K−π+π+)B(Λ0c→pK−π−)=(5.35±0.21±0.16)%, where the first uncertainty is statistical and the second systematic. The ratio of branching fractions for the Λ0b → D*+pπ−π− and Λ0b → D+pπ−π− decays is found to be B(Λ0b→D∗+pπ−π−)B(Λ0b→D+pπ−π−)×(B(D∗+→D+π0)+B(D∗+→D+γ))=(61.3±4.3±4.0)%