Systematic analysis of the form factors of $B_c\rightarrow\eta_c$, $J/\psi$ and corresponding weak decays

TL;DR

This paper calculates the form factors of B_c meson decays to eta_c and J/psi using QCD sum rules, including vacuum condensate effects, and predicts decay widths and branching ratios to aid heavy-quark physics and new physics searches.

Contribution

It provides a systematic analysis of B_c decay form factors with vacuum condensate contributions, offering new theoretical predictions for decay properties.

Findings

Calculated form factors for B_c decays to eta_c and J/psi.

Predicted decay widths and branching ratios for various decay channels.

Enhanced understanding of heavy-quark dynamics and potential new physics signals.

Abstract

The form factors of $B_c\rightarrow\eta_c$ and $B_c\rightarrow J/\psi$ are analyzed in the framework of three-point QCD sum rules. In these analyses, the contributions of the vacuum condensate terms $\langle g_{s}^{2}GG\rangle$ and $\langle g_{s}^{3}GGGf\rangle$ are considered. In addition, the decay widths and branching ratios of several decay channels are obtained by using the calculated form factors. These decay processes include the nonleptonic decays of $B_c^- \to \eta_c \pi^-$, $\eta_c K^-$, $\eta_c \rho^-$, $\eta_c K^{*-}$, $B_c^- \to J/\psi \pi^-$, $J/\psi K^-$, $J/\psi \rho^-$, $J/\psi K^{*-}$, and the semileptonic decays of $B_c^- \to \eta_c \mathcal{l} \bar{\nu}$, $B_c^- \to J/\psi \mathcal{l} \bar{\nu}$. These results about the form factors and decay properties of $B_c$ meson provide useful information for us to study the heavy-quark dynamics and find new physics(NP) beyond Standard Model(SM).