Analysis of Two-body Charmed $B$ Meson Decays in Factorization-Assisted Topological-Amplitude Approach

TL;DR

This paper employs a factorization-assisted topological-amplitude approach to analyze two-body charmed B meson decays, incorporating SU(3) symmetry breaking effects, reducing free parameters, and predicting numerous decay modes with results consistent with experimental data.

Contribution

It introduces a simplified, SU(3)-breaking inclusive method with only four universal parameters to analyze B meson decays, improving upon traditional approaches.

Findings

Predicted branching fractions align with experimental data.

Identified SU(3) symmetry breaking and isospin violation effects.

Provided predictions for 120 decay modes, testable at LHCb and Belle-II.

Abstract

Within the factorization-assisted topological-amplitude approach, we study the two-body charmed $B$ meson decays $B_{u,d,s} \to D^{(*)}M$, with $M$ denoting a light pseudoscalar (or vector) meson. The meson decay constants and transition form factors are factorized out from the hadronic matrix element of topological diagrams. Therefore the effect of SU(3) symmetry breaking is retained, which is different from the conventional topological diagram approach. The number of free nonperturbative parameters to be fitted from experimental data is also much less. Only four universal nonperturbative parameters $\chi^C$, $\phi^C$, $\chi^E$ and $\phi^E$ are introduced to describe the contribution of the color suppressed tree and $W$-exchanged diagrams for all the decay channels. With the fitted parameters from 31 decay modes induced by $b\to c$ transition, we then predict the branching fractions of 120 decay modes induced by both $b\to c$ and $b\to u$ transitions. Our results are well consistent with the measured data or to be tested in the LHCb and Belle-II experiments in the future. Besides, the SU(3) symmetry breaking, isospin violation and $CP$ asymmetry are also investigated.