Taming New Physics in $b \to c \bar u d (s) $ with $τ(B^+)/τ(B_d)$ and $a_{sl}^d$

Alexander Lenz; Jakob Müller; Maria Laura Piscopo; Aleksey V. Rusov

paper

Taming New Physics in $b \to c u ˉ d (s)$ with $τ (B^{+}) / τ (B_{d})$ and $a_{s l}^{d}$

arXiv:2211.02724

Abstract

Inspired by the recently observed tensions between the experimental data and the theoretical predictions, based on QCD factorisation, for several colour-allowed non-leptonic $B$ -meson decays, we study the potential size of new physics (NP) effects in the decay channels $b \to c u ˉ d (s)$ . Starting from the most general effective Hamiltonian describing the $b \to c u ˉ d (s)$ transitions, we compute NP contributions to the theoretical predictions of $B$ -meson lifetime and of $B$ -mixing observables. The well-known lifetime ratio $τ (B^{+}) / τ (B_{d})$ and the experimental bound on the semi-leptonic CP asymmetry $a_{s l}^{d}$ , provide strong, complementary constraints on some of the NP Wilson coefficients.

29 pages, 3 figures

Taming New Physics in b→cuˉd(s) with τ(B+)/τ(Bd​) and asld​

Abstract

Taming New Physics in $b \to c u ˉ d (s)$ with $τ (B^{+}) / τ (B_{d})$ and $a_{s l}^{d}$