$B$ anomalies in the nonminimal universal extra dimension model

Abstract

We investigate the $B$ anomalies in the framework of the nonminimal universal extra dimension models. Newly measured polarization parameters in $B\to D^{(*)}\tau\nu$, $P_\tau(D^{(*)})$ and $F_L(D^*)$ as well as the ratios $R(D^{(*)})$ are considered altogether. The Kaluza-Klein modes of the $W$-boson and charged scalar contributes as the new physics effects. We find that the model parameters fit the global data very well with the minimum $\chi^2/{\rm d.o.f.}$ near unity, rendering $B_c\to\tau\nu$ branching ratios to be a few percents. The best-fit values of $R(D)$ and $R(D^*)$ are still far from ($\gtrsim 2\sigma$) the standard model predictions.