Search for Bc+→π+μ+μ-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{B} _{c} ^+} \\!\\rightarrow {{\\pi } ^+} {\\mu ^+\\mu ^-} $$\\end{document} decays and measurement of the branching fraction ratio B(Bc+→ψ(2S)π+)/B(Bc+→J/ψπ+)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\mathcal {B}} ({{B} _{c} ^+} \\!\\rightarrow {\\psi {(2S)}} {{\\pi } ^+} )/{\\mathcal {B}} ({{B} _{c} ^+} \\!\\rightarrow {{J \\hspace{-1.66656pt}/\\hspace{-1.111pt}\\psi }} {{\\pi

Abstract

The first search for nonresonant Bc+→π+μ+μ-\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{B} _{c} ^+} \\!\\rightarrow {{\\pi } ^+} {\\mu ^+\\mu ^-} $$\\end{document} decays is reported. The analysis uses proton–proton collision data collected with the LHCb detector between 2011 and 2018, corresponding to an integrated luminosity of 9fb-1\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\,\ ext {fb} ^{-1}$$\\end{document}. No evidence for an excess of signal events over background is observed and an upper limit is set on the branching fraction ratio B(Bc+→π+μ+μ-)/B(Bc+→J/ψπ+)<2.1×10-4\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\mathcal {B}} ({{B} _{c} ^+} \\!\\rightarrow {{\\pi } ^+} {\\mu ^+\\mu ^-} )/{\\mathcal {B}} ({{B} _{c} ^+} \\!\\rightarrow {{J \\hspace{-1.66656pt}/\\hspace{-1.111pt}\\psi }} {{\\pi } ^+} ) < 2.1\ imes 10^{-4}$$\\end{document} at 90%\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$90\\%$$\\end{document} confidence level. Additionally, an updated measurement of the ratio of the Bc+→ψ(2S)π+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{B} _{c} ^+} \\!\\rightarrow {\\psi {(2S)}} {{\\pi } ^+} $$\\end{document} and Bc+→J/ψπ+\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${{B} _{c} ^+} \\!\\rightarrow {{J \\hspace{-1.66656pt}/\\hspace{-1.111pt}\\psi }} {{\\pi } ^+} $$\\end{document} branching fractions is reported. The ratio B(Bc+→ψ(2S)π+)/B(Bc+→J/ψπ+)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\mathcal {B}} ({{B} _{c} ^+} \\!\\rightarrow {\\psi {(2S)}} {{\\pi } ^+} )/{\\mathcal {B}} ({{B} _{c} ^+} \\!\\rightarrow {{J \\hspace{-1.66656pt}/\\hspace{-1.111pt}\\psi }} {{\\pi } ^+} )$$\\end{document} is measured to be 0.254±0.018±0.003±0.005\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$0.254\\pm 0.018 \\pm 0.003 \\pm 0.005$$\\end{document}, where the first uncertainty is statistical, the second systematic, and the third is due to the uncertainties on the branching fractions of the leptonic J/ψ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${J \\hspace{-1.66656pt}/\\hspace{-1.111pt}\\psi }$$\\end{document} and ψ(2S)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\psi {(2S)}$$\\end{document} decays. This measurement is the most precise to date and is consistent with previous LHCb results.