Unified explanation of flavor anomalies, radiative neutrino mass and ANITA anomalous events in a vector leptoquark model

Driven by the recent experimental hints of lepton-flavor-universality violation in the bottom-quark sector, we consider a simple extension of the Standard Model (SM) with an additional vector leptoquark $V_{\rm LQ}({\bf 3},{\bf 1},2/3)$andascalardiquark$S_{\rm DQ}({\bf 6},{\bf 1},4/3)$ under the SM gauge group $SU(3{)}_c\times SU(2{)}_L\times U(1{)}_Y$, in order to simultaneously explain the $b\to s{\mathrm{\ell }}^{+}{\mathrm{\ell }}^{-}$ (with $\mathrm{\ell }=e,\mu$) and $b \to c l^- \bar \nu_l$(with$l=e,\mu,\tau$) flavor anomalies, as well as to generate small neutrino masses through a two-loop radiative mechanism. We perform a global fit to all the relevant and up-to-date $b\to s{\mathrm{\ell }}^{+}{\mathrm{\ell }}^{-}$ and $b\to c{l}^{-}{\bar{\nu }}_l$ data under the assumption that the leptoquark couples predominantly to second and third-generation SM fermions. We then look over the implications of the allowed parameter space on lepton-flavor-violating $B$ and $\tau$ decay modes, such as $B_s \to l^+_i l^-_j, \ B \to K^{(*)} l^+_i l^-_j, \ B_s \to \phi l^+_i l^-_j$,$\Upsilon(nS) \to \mu \tau$and$\tau \to \mu \gamma$,$\tau \to \mu \phi (\eta^{(\prime)})$, respectively. Minimally extending this model by adding a fermion singlet $\chi (\mathbf{1},\mathbf{1},0)$ also explains the ANITA anomalous upgoing events. Furthermore, we provide complementary constraints on leptoquark and diquark couplings from high-energy collider and other low-energy experiments to test this model.