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

TL;DR

This paper investigates $CP$ violation in specific baryon decays using a rescattering mechanism, predicting measurable asymmetries and branching ratios that align with current data and can be tested in future experiments.

Contribution

It introduces a rescattering model with two parameters to analyze $CP$ violation in baryon decays, providing predictions consistent with existing measurements and guiding future experimental tests.

Findings

Predicted branching ratios match current experimental data.

Identified large $CP$ asymmetries in certain decay channels.

Results suggest future experiments can test the predicted $CP$ violation effects.

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.