A closer look at observables from exclusive semileptonic B → (π, ρ)lνl decays

This article analyses the available inputs in B -> pi l nu(l) and B -> rho l nu(l) decays which include the measured values of differential rate in different q(2)-bins (lepton invariant mass spectrum), lattice, and the newly available inputs on the relevant form-factors from the light-cone sum rules (LCSR) approach. We define different fit scenarios, and in each of these scenarios, we predict a few observables in the standard model (SM). For example, R(M) = B(B -> Ml(i)nu(li))/B(B -> Ml(j)nu(lj)), R-lj(li) (M) = B(B -> l(i)nu(li))/B(B -> Ml(j)nu(lj)) with M = pi or rho and l(i,j) = e, mu or tau. We also discuss the new physics (NP) sensitivities of all these observables and obtain bounds on a few NP Wilson coefficients in b -> u tau nu(tau) decays using the available data. We have noted that the data at present allows sizeable NP contributions in this mode. Also, we have predicted a few angular observables relevant to these decay modes.

Automated summary

This article analyzes the available inputs and observables in different decay modes of B mesons, predicting some quantities in the standard model while discussing their sensitivities to new physics. It also obtains bounds on new physics Wilson coefficients in b -> u tau nu(tau) decays using existing data and predicts angular observables relevant to these decay modes.