Study of the kinematic dependences of Λb0 production in pp collisions and a measurement of the Λb0 → Λc+π− branching fraction

The kinematic dependences of the relative production rates, fΛb0/fd\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {f}_{\varLambda_b^0}/{f}_d $$\end{document}, of Λb0 baryons and B0 mesons are measured using Λb0 → Λc+π− and B¯0→D+π−\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\overline{B}}^0\ \to {D}^{+}{\pi}^{-} $$\end{document} decays. The measurements use proton-proton collision data, corresponding to an integrated luminosity of 1 fb−1 at a centre-of-mass energy of 7 TeV, recorded in the forward region with the LHCb experiment. The relative production rates are observed to depend on the transverse momentum, pT, and pseudorapidity, η, of the beauty hadron, in the studied kinematic region 1.5 < pT< 40 GeV/c and 2 < η < 5. Using a previous LHCb measurement of fΛb0/fd\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {f}_{\varLambda_b^0}/{f}_d $$\end{document} in semileptonic decays, the branching fraction ℬ(Λb0 → Λc+π−) = (4.30 ± 0.03− 0.11+ 0.12 ± 0.26 ± 0.21) × 10− 3 is obtained, where the first uncertainty is statistical, the second is systematic, the third is from the previous LHCb measurement of fΛb0/fd\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {f}_{\varLambda_b^0}/{f}_d $$\end{document} and the fourth is due to the b B¯0→D+π−\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ {\overline{B}}^0\ \to {D}^{+}{\pi}^{-} $$\end{document} branching fraction. This is the most precise measurement of a Λb0 branching fraction to date. [graphic not available: see fulltext]