• DOI:10.1007/JHEP10(2020)163
• Corpus ID: 220514830

Relations between b → cτν decay modes in scalar models

@article{Schacht2020RelationsBB,
  title={Relations between b → c$\tau$$\nu$ decay modes in scalar models},
  author={Stefan Schacht and Amarjit Soni},
  journal={Journal of High Energy Physics},
  year={2020},
  volume={2020}
}

• S. Schacht, A. Soni
• Published 13 July 2020
• Physics
• Journal of High Energy Physics

As a consequence of the Ward identity for hadronic matrix elements, we find relations between the differential decay rates of semileptonic decay modes with the underlying quark-level transition b → cτν, which are valid in scalar models. The decay-mode dependent scalar form factor is the only necessary theoretical ingredient for the relations. Otherwise, they combine measurable decay rates as a function of the invariant mass-squared of the lepton pair q2 in such a way that a universal decay-mode independent function is found for decays to vector and pseudoscalar mesons, respectively. This can be applied to the decays B→D∗τv,Bs→Ds∗τv,Bc→J/ψτv\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ B\to {D}^{\ast}\tau v,{B}_s\to {D}_s^{\ast}\tau v,{B}_c\to J/\psi \tau v $$\end{document} and B → Dτv, Bs → Dsτv, Bc → ηcτv, with implications for R(D(*)), RDs∗\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ R\left({D}_s^{\left(\ast \right)}\right) $$\end{document}, R(J/ψ), R(ηc), and ℬ(Bc → τv). The slope and curvature of the characteristic q2-dependence is proportional to scalar new physics parameters, facilitating their straight forward extraction, complementary to global fits.