$\mathcal{R}(D^{(\ast )})$ anomalies in light of Non-Minimal Universal Extra Dimension

Abstract

We estimate contributions from Kaluza-Klein excitations of gauge bosons and physical charge scalar for the explanation of the lepton flavor universality violating excess in the ratios $\mathcal{R}(D)$ and $\mathcal{R}(D^{\ast })$ in 5 dimensional Universal Extra Dimensional scenario with non-vanishing boundary localized terms. This model is conventionally known as non-minimal Universal Extra Dimensional model. We obtain the allowed parameter space in accordance with constraints coming from $B_c\to \tau \nu$ decay, as well as those from the electroweak precision tests.

Comments: 14 pages, 7 captioned figures, Some clarifications and corrections added (Version accepted in PRD)