Lepton flavor (universality) violation in $B$-meson decays

Abstract: Even though the LHC searches did not unveil the new physics particles so far, LHCb hints towards deviations from lepton flavor universality in exclusive decays based on the transition $b\to s\ell\ell$. In this proceeding, we present a new leptoquark model that can explain both $R_{K}^{\mathrm{exp}}<R_{K}^{\mathrm{SM}}$ and $R_{K^\ast}^{\mathrm{exp}}<R_{K^\ast}^{\mathrm{SM}}$ via loop effects, consistent with observations made by LHCb. We discuss the main predictions of this scenario that can be tested experimentally, which include the bounds on lepton flavor violating decays $\mathcal{B}(Z\to\mu\tau) \lesssim \mathcal{O}(10^{-7})$ and $\mathcal{B}(B\to K\mu\tau)\lesssim \mathcal{O}(10^{-9})$.