Speaker
Description
Observations of flavor anomalies in the $b$-sector, particularly the deviations in the measurements of the lepton flavor universality ratios in the $b \rightarrow c \tau \nu_\tau$ transitions from the standard model (SM) predictions, suggest the existence of possible new physics beyond the SM. In the pursuit of new physics in similar decays involving $b\to c \ell \nu_{\ell}$ transitions, we scrutinize the decay modes $\Lambda_b \to \Lambda_{c}^{*}(2595,2625) \tau^- \bar{\nu}_\tau$ beyond the SM. In particular, we examine the impact of the presence of leptoquarks in these decay modes, within the framework of the vector leptoquark $U_1$ model. We employ form factors obtained from lattice QCD (LQCD) calculations to predict various $q^2$-dependent observables. Some of these observables include the differential branching fraction, the ratio of branching fractions and the forward-backward asymmetry of the charged lepton. The new couplings are constrained using current $b \to c \ell \nu_{\ell}$ experimental data.
