$b\to c \bar u q$ decay and CP violating observables in the presence of new physics contributions

Abstract

In this work, a comprehensive analysis for processes related to $b\to c\bar{u}q~(q=d, s)$ transitions are carried out, including new physics contributions. In light of a recent tension between branching fractions for $B_{(s)}\to D_{(s)}^{(*)}M$ ($M$ represents a meson) decays in the QCD factorization approach and relevant experimental results, phenomenological constraints on complex-valued Wilson coeffients are discussed. Analyzed observables contain direct CP asymmetry ($A_{\text{CP}}$) in $B^-\to D^0\pi^-$ decays and $\gamma/\phi_3$, one of the angles in the unitarity triangle, combined with others from $\tau_{B^+}/\tau_{B_d}$, $\Delta\Gamma_{q}/\Gamma_q$, and $A_{\rm SL}^{q}~(q=d, s)$. We constrain the complex Wilson coefficients at $1\sigma$ and $2\sigma$ levels under color-singlet and color-rearranged scenarios. These constraints yield correlated predictions for $\Delta\Gamma_d/\Gamma_d$, $A_{\rm SL}^d$ and $A_{\text{CP}}$.