Title:

On new physics in nonleptonic tree level bquark decays and hadronquark duality violations

We review the validity of the assumption of having no new physics in tree level b quark transitions $b\rightarrow q q' d$ and $b\rightarrow q q' s$ ($q, q'= u,c$). In particular we test for possible deviations on the Wilson coefficients of the corresponding effective currentcurrent operators with respect to their Standard Model values. The allowed new physics regions are determined using a global fit. We take into account constraints from different flavour observables calculated from the hadronic decays $B^0_d\rightarrow \pi\pi$, $B^0_d\rightarrow \rho\pi$, $B^0_d\rightarrow \rho\rho$, $B\rightarrow X_s \gamma$ and $B\rightarrow X_d \gamma$. We also include observables from neutral B meson mixing such as $\Delta \Gamma_s$ and the semileptonic asymmetries $a^{s,d}_{sl}$. We show that deviations in the tree level Wilson coefficients of the order $\mathcal{O}(10\%)$ are consistent with state of the art experimental measurements. We study the implications of these deviations over the decay width $\Delta \Gamma_d$ of $B^0_d$ meson mixing, not measured yet by experiments, and over the precision of the CKM phase $\gamma$. Our results show that enhancements on $\Delta \Gamma_d$ by up to a factor of 3.6 with respect to the Standard Model value are allowed by data. Moreover the effects on $\gamma$ can compete with the corresponding experimental precision $\mathcal{O}(6^{\circ})$. Finally we explore for possible hadronquark duality violations in the neutral $B$ and $D$ meson sectors. This analysis includes constraints from mixing observables and from the lifetimes of $B^0_d$ and $B^0_s$ mesons. We find that duality violations of $\mathcal{O}(20\%)$ can provide an explanation to the tension of several orders of magnitude between the Heavy Quark Expansion and experimental data in the observable $\Delta \Gamma_D$ of neutral $D$ meson mixing.
