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Model independent analysis of $ B^* to P ell bar{ u}_ell$ decay processes

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 نشر من قبل Dr. Rukmani Mohanta
 تاريخ النشر 2019
  مجال البحث
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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.

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