Study of $CP$ violation in $\Lambda_b^0/\Xi^-_b\rightarrow \Lambda(1520)M$ decays with the final-state rescattering mechanism

Abstract

Recently, the LHCb collaboration reported the first observation of $CP$ violation in baryon decays, with a significance of more than $5\sigma$. This strongly motivates us to investigate the $CP$ violation in more baryon decay processes. In this work, we employ the final-state rescattering mechanism with introducing two model parameters, $\Lambda_{charm}$ and $\Lambda_{charmless}$, and calculate two-body non-leptonic baryon decays $\Lambda^0_b \rightarrow \Lambda(1520)\,\pi^0/\kappa(700)/f_0(500, 980)/\rho^0/K^{*0}/\phi$ and $\Xi^-_b \rightarrow \Lambda(1520)\,K^-$. Consequently, we evaluate the corresponding branching ratios, $CP$ asymmetries, and interference effects between different decay amplitudes. Our theoretical predictions for certain decay channels are in good agreement with current experimental measurements, while the remaining processes--particularly the remarkably large $CP$ violation observable revealed by the kinematic analysis are expected to be tested in future experiments.