Observation of the decays Bs0\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ {B}_{(s)}^0 $$\\end{document} → Ds1(2536)∓K±

Abstract

This paper reports the observation of the decays Bs0\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ {B}_{(s)}^0 $$\\end{document} → Ds1(2536)∓K± using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9 fb−1. The branching fractions of these decays are measured relative to the normalisation channel B0→D¯\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\overline{D} $$\\end{document}0K+K−. The Ds1(2536)− meson is reconstructed in the D¯\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\overline{D} $$\\end{document}*(2007)0K− decay channel and the products of branching fractions are measured to beBBs0→Ds12536∓K±×BDs12536−→D¯∗20070K−=2.49±0.11±0.12±0.25±0.06×10−5,BB0→Ds12536∓K±×BDs12536−→D¯∗20070K−=0.510±0.021±0.036±0.050×10−5.\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ {\\displaystyle \\begin{array}{c}\\mathcal{B}\\left({B}_s^0\ o {D}_{s1}{(2536)}^{\\mp }{K}^{\\pm}\\right)\ imes \\mathcal{B}\\left({D}_{s1}{(2536)}^{-}\ o {\\overline{D}}^{\\ast }{(2007)}^0{K}^{-}\\right)\\\\ {}=\\left(2.49\\pm 0.11\\pm 0.12\\pm 0.25\\pm 0.06\\right)\ imes {10}^{-5},\\\\ {}\\mathcal{B}\\left({B}^0\ o {D}_{s1}{(2536)}^{\\mp }{K}^{\\pm}\\right)\ imes \\mathcal{B}\\left({D}_{s1}{(2536)}^{-}\ o {\\overline{D}}^{\\ast }{(2007)}^0{K}^{-}\\right)\\\\ {}=\\left(0.510\\pm 0.021\\pm 0.036\\pm 0.050\\right)\ imes {10}^{-5}.\\end{array}} $$\\end{document}The first uncertainty is statistical, the second systematic, and the third arises from the uncertainty of the branching fraction of the B0→D¯\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\overline{D} $$\\end{document}0K+K− normalisation channel. The last uncertainty in the Bs0\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ {B}_s^0 $$\\end{document} result is due to the limited knowledge of the fragmentation fraction ratio, fs/fd. The significance for the Bs0\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ {B}_s^0 $$\\end{document} and B0 signals is larger than 10 σ. The ratio of the helicity amplitudes which governs the angular distribution of the Ds1(2536)−→D¯\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$ \\overline{D} $$\\end{document}*(2007)0K− decay is determined from the data. The ratio of the S- and D-wave amplitudes is found to be 1.11 ± 0.15 ± 0.06 and the phase difference between them 0.70 ± 0.09 ± 0.04 rad, where the first uncertainty is statistical and the second systematic.