Probing new physics in semileptonic Xi _{b}rightarrow Lambda (Xi _{c})tau ^{-}bar{nu }_{tau } decays

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Recently, several observed anomalies in semileptonic B meson decays have implied hints of lepton flavor universal violation. Motivated by these inspiring results, we study the baryon decays Xi _{b}rightarrow Lambda (Xi _{c})tau ^{-}bar{nu }_{tau } which are mediated by brightarrow u(c)tau ^{-}bar{nu }_{tau } transitions at quark level in the Standard Model and different New Physics scenarios. In the framework of the extended Standard Model on assuming a general effective theory, we constrain the Wilson coefficients of the NP operators using the experimental measurement results for the Br(B_{c}^+rightarrow tau ^+ nu _{tau }), R^{l}_{pi }, R_{D^{(*)}}, R_{J/psi } and F_{L}^{D^{*}} anomalies and investigate their New Physics effects on several observables relative to the Xi _{b}rightarrow Lambda (Xi _{c})tau ^{-}bar{nu }_{tau } decays. We mention the differential branching fraction {text {d}}Br/{text {d}}q^2, the ratio of branching fractions R(q^2), the lepton-side forward–backward asymmetry A_{FB}(q^2), the longitudinal polarization P_{L}^{Lambda (Xi _{c})}(q^2) of the daughter baryons Lambda (Xi _{c}) and P_{L}^{tau }(q^2) of the tau lepton, and the convexity parameter C_{F}(q^2).