R(D) and R(D*) anomalies and their phenomenological implications

Recently, BaBar, Belle and LHCb have found hints of lepton flavour universality violation in B→D(⁎)τν‾τ decays, i.e., the measured ratios R(D(⁎))=B(B→D(⁎)τν‾τ)/B(B→D(⁎)ℓν‾ℓ)(ℓ=e/μ) show a combined 3.8 σ deviation from the SM predictions. In this talk, we will discuss two possible solutions to the observed R(D) and R(D*) anomalies: one with an EW-scale charged scalar and the other with a TeV-scale scalar leptoquark transforming as (3, 1, −13) under the SM gauge group. Their phenomenological implications for the other decays are also briefly discussed.