Implications for new physics from a novel puzzle in ${\bar{B}}_{(s)}^0\to D_{(s)}^{(\ast )+}\{{\pi }^{-},K^{-}\}$ decays

Abstract

Recently, the standard model predictions for the $B$-meson hadronic decays, ${\bar{B}}^0\to D^{(\ast )+}{K}^{-}$ and ${\bar{B}}_s^0\to D_s^{(\ast )+}{\pi }^{-}$, have been updated based on the QCD factorization approach. This improvement sheds light on a novel puzzle in the $B$-meson hadronic decays: there are mild but universal tensions between data and the predicted branching ratios. Assuming the higher-order QCD corrections are not huge enough to solve the tension, we examine several new physics interpretations of this puzzle. We find that the tension can be partially explained by a left-handed $W^{\prime }$ model, which can be compatible with other flavor observables and collider bounds.

9 pages, 1 figure; v2: references added; v3: version published as a Rapid Communication in PRD