Implication of family non-universal $Z'$ model to rare exclusive $b \to s(l\bar l,\nu\bar\nu)$ transitions

Understand

We have investigated $B \to (K,K^*)(l\bar l,\nu\bar\nu)$ decay channels and predicted some form factor dependent observables (e.g.

• branching ratio, forward-backward asymmetry and lepton polarization asymmetry) considering new physics contribution from non-universal $Z'$ model.
• We have found that there is appreciable difference between the standard model and $Z'$ model predictions.
• Recently, the lepton flavour non-universality parameters $R_K$ and $R_{K^*}$ have been measured by the LHCb collaboration and are found to be different from their standard model predictions.