Speaker
Description
Motivated by the interplay between the LEFT and SMEFT operators at the electroweak scale, we study the interrelation among the transitions $b \to c \ell \nu_{\ell}$, $b \to s \nu _\ell \nu _\ell$ and $b \to s\ell \ell$ ($\ell = e, \mu, \tau$). We explore this correlation within the context of six - SMEFT operators: $\mathcal{Q}_{\ell q}^{(3)}$, $\mathcal{Q}_{\ell ed q}$, $\mathcal{Q}_{\ell e qu}^{(1)}$, $\mathcal{Q}_{\ell e qu}^{(3)}$, $\mathcal{Q}_{\phi q}^{(3)}$ and $\mathcal{Q}_{\ell q}^{(1)}$.
We constrain the new physics parameter space through a comprehensive global fit incorporating the observables: $R_D$, $R_{D^*}$, $P_{\tau}(D)$, $P_{\tau}(D^*)$, $F_L(D^*)$, $\mathcal{B}(B_0 \to K^* \nu \nu)$, $\mathcal{B}(B \to K^+ \nu \nu)$, $\mathcal{B}(B \to K^+ \tau^+ \tau^-)$ and $\mathcal{B}(B_s \to \tau^+ \tau^-)$. We then investigate the sensitivity of new physics in the semileptonic decay modes of b-baryons, specifically $\Xi_b \to \Xi_c \tau^-\bar{\nu}_\tau$ and $\Sigma_b \to \Sigma_c^{(*)} \tau^{-}\bar{\nu}_\tau$. We also provide the predictions of several observables such as the branching ratio, forward-backward asymmetry, longitudinal polarisation asymmetry, convexity parameter, and the lepton flavor non-universality observable of $\Xi_b \to \Xi_c \tau^-\bar{\nu}_\tau$ and $\Sigma_b \to \Sigma_c^{(*)} \tau^-\bar{\nu}_\tau$ processes.
