New physics effects in semileptonic $\bar{B_s} \to K^{*+}(\to Kπ) \ell^- \barν_\ell$ decay

Abstract: In this work, we analyze the new physics effects in semileptonic decay $\bar{B_s} \to K^{*+}(\to K\pi) \ell^- \bar{\nu}\ell$ induced by the $b \to u \ell \nu{\ell}$ quark level transition. We consider the vector, axial vector, scalar, pseudoscalar and tensor new physics Lorentz structures in addition to the SM in effective field theory approach. New physics wilson coefficients are contrained by the available experimental measurements of leptonic and semileptonic decays of $B$ mesons induced by the same quark level transition $b \to u \ell \nu_{\ell}$. We explore the new physics effects in differential branching fraction, lepton forward-backward asymmetry and longitudinal polarization fraction of $K^*$ meson in $\bar{B_s} \to K^{*+}(\to K\pi) \ell^- \bar{\nu}_\ell$ decay. In addition, we also provide the predictions for the integrated values of normalized angular obseravbles in different new physics scenarios.