Abstract
This article analyses the available inputs in B → πℓνℓ and B → ρℓνℓ decays which include the measured values of differential rate in different q2-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, \( R(M)=\frac{\mathcal{B}\left(B\to M{\ell}_i{\nu}_{\ell_i}\right)}{\mathcal{B}\left(B\to M{\ell}_j{\nu}_{\ell_j}\right)},{R}_{\ell_j}^{\ell_i}(M)=\frac{\mathcal{B}\left(B\to {\ell}_i{\nu}_{\ell_i}\right)}{\mathcal{B}\left(B\to M{\ell}_j{\nu}_{\ell_j}\right)} \) with M = π or ρ and ℓi,j = e, μ or τ. We also discuss the new physics (NP) sensitivities of all these observables and obtain bounds on a few NP Wilson coefficients in b → uτντ 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.
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Biswas, A., Nandi, S. A closer look at observables from exclusive semileptonic B → (π, ρ)ℓνℓ decays. J. High Energ. Phys. 2021, 127 (2021). https://doi.org/10.1007/JHEP09(2021)127
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DOI: https://doi.org/10.1007/JHEP09(2021)127