Speaker
Description
This study investigates the decay modes of the $B_{c}$ meson, focussing on semileptonic decays into S and P wave charmonia. The primary objective is to extract the shape parameter of the $B_{c}$ meson distribution amplitude through a data-driven approach, utilizing $B_{c}\rightarrow\eta_{c},J/\psi$ form factors in modified perturbative QCD framework. Further, by employing heavy quark spin symmetry, shape of $B_{c}\rightarrow\eta_{c}$ form factor is derived from existing lattice results of $B_{c}\rightarrow J/\psi$ form factors, giving a model-independent prediction of LFUV observable $R(\eta_{c})=0.304(36)$, which we have found to be in good agreement with previous results. Additionally, we have extracted the decay constants of $P$ wave charmonium states, $\chi_{c0}$, $\chi_{c1}$ and $h_{c}$ through their radiative decay modes, providing a data-driven alternative to existing model dependent values, enabling us to use them as inputs to predict the $B_{c}\rightarrow\text{ }P$ wave form factors at $q^{2}=0$ within the modified perturbative QCD framework. Subsequently, utilizing the shapes of the $B_{c}\rightarrow\eta_{c}$ and $J/\psi$ form factors, we have obtained $q^{2}$ distribution of the $B_{c}\rightarrow\chi_{c0},\chi_{c1}$ and $h_{c}$ form factors through pole expansion parametrization, using which we obtain predictions of LFUV observables $R(\chi_{c0})=0.195(4)$, $R(\chi_{c1})=0.129(7)$ and $R(h_{c})=0.109(4)$.
| Field of contribution | Phenomenology |
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