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Very compelling deviations in the recently observed lepton nonuniversality observables $big (R_{D^{(*)}}, R_{K^{(*)}}, R_{J/psi} big )$ of semileptonic $B$ meson decays from their Standard Model predictions hint towards the presence of some kind of new physics beyond it. In this regard, we investigate the effect of new physics in the semileptonic $bar B_{d(s)}^* to P ell bar{ u}_ell$ decay processes, where $P=D,pi (D_s,K$), in a model independent way. We consider the presence of additional vector and scalar type interactions and constrain the corresponding new couplings by fitting ${rm Br(B_{u}^+ to tau^+ u_tau)}$, ${rm Br(B to pi tau bar u_tau)}$, ${rm Br(B_{c}^+ to tau^+ u_tau)}$, $R_pi^l$, $R_{D^{(*)}}$ and $R_{J/psi}$ data. Using the constrained new parameters, we estimate the branching ratios, forward-backward asymmetry, lepton-spin asymmetry and lepton non-universality observables of $bar B_{d,s}^{*} to P tau bar u_tau$ processes. We find that the branching ratios of these decay modes are sizeable and deviate significantly (for vector-type couplings) from their corresponding standard model values, which are expected to be within the reach of Run III of Large Hadron Collider experiment.
We comprehensively study the charged-Higgs contributions to the leptonic $B^-_q to ell bar u$ ($q=u,c$) and semileptonic $bar B to X_q ell bar u$ ($X_u=pi, rho; X_c=D,D^*$) decays in the type-III two-Higgs-doublet model (2HDM). We employ the Cheng-S
We report a measurement of the branching fraction ratios R(D(*)) of Bbar -> D(*) tau- nubar_tau relative to Bbar -> D()* l- nubar_l (where l = e or mu) using the full Belle data sample of 772 x 10^6 BBbar pairs collected at the Y(4S) resonance with t
A new model-independent parametrization is proposed for the hadronic form factors in the semileptonic $bar{B}to Dellbar{ u}_ell$ decay. By a combined consideration of the recent experimental and lattice QCD data, we determine precisely the Cabibbo-Ko
Experimental data on $ R(D^{(*)}) $, $ R(K^{(*)}) $ and $ R(J/psi) $, provided by different collaborations, show sizable deviations from the SM predictions. To describe these anomalies many new physics scenarios have been proposed. One of them is lep
We study model-independently the implications of non-standard scalar and pseudoscalar interactions for the decays b ->s gamma, b -> s g, b -> s l^+l^- (l=e,mu) and B_s -> mu^+ mu^-. We find sizeable renormalization effects from scalar and pseudoscala