Explaining the B d , s → K ∗ K ¯ ∗ $$ {B}_{d,s}\to {K}^{\left(\ast \right)}{\overline{K}}^{\left(\ast \right)} $$ non-leptonic puzzle and charged-current B-anomalies via scalar leptoquarks

Abstract We present a model based on S 1 scalar leptoquarks to solve the tension observed in the recently proposed non-leptonic optimized observables L K ∗ K ¯ ∗ $$ {L}_{K^{\ast }{\overline{K}}^{\ast }} $$ and L K K ¯ $$ {L}_{K\overline{K}} $$ . These observables are constructed as ratios of U-spin related decays based on B d , s 0 → K ∗ 0 K ¯ ∗ 0 $$ {B}_{d,s}^0\to {K}^{\left(\ast \right)0}{\overline{K}}^{\left(\ast \right)0} $$ . The model gives a one-loop contribution to the Wilson coefficient of the chromomagnetic dipole operator needed to explain the tension in both non-leptonic observables, while naturally avoiding large contributions to the corresponding electromagnetic dipoles. The necessary chiral enhancement comes from an O(1) Yukawa coupling with a TeV-scale right-handed neutrino running in the loop. We endow the model with a U(2) flavor symmetry, necessary to protect light-family flavor observables that otherwise would be in tension. Furthermore, we show that the same S 1 scalar leptoquark is capable of simultaneously explaining the hints of lepton flavor universality violation observed in charged-current B-decays. The model therefore provides a potential link between two puzzles in B-physics and TeV-scale neutrino mass generation. Finally, the combined explanation of the B-physics puzzles unavoidably results in an enhancement of B B → Kν ν ¯ $$ \mathcal{B}\left(B\to K\nu \overline{\nu}\right) $$ , yielding a value close to present bounds.