CP Violation of Baryon Decays with $N\pi$ Scatterings

Abstract

There is a long-standing puzzle that the CP violation (CPV) in the baryon systems has never been well established in experiments, while the CPV of mesons have been observed by decades. In this paper, we propose that the CPV of baryon decays can be generated with the rescatterings of a nucleon and a pion into some final states, i.e. $N\pi \to N\pi$ or $N\pi \pi$. Benefited by the fruitful data of $N\pi$ scatterings, we can model-independently analyse the strong phases of $b$-baryon decays using the partial wave amplitudes of $N\pi$ scatterings. Avoiding the most difficult problem of non-perturbative dynamics, it makes a great advantage to predict the CPV of baryon decays with a relatively reliable understanding of the decay dynamics. We study the processes of ${\Lambda }_b^0\to (p{\pi }^{+}{\pi }^{-})h^{-}$ and $(p{\pi }^0)h^{-}$ with $h=\pi$ or $K$. It is found that the global CPV of the above processes in the invariant mass regions of $N\pi$ scatterings are at the order of several percent. More importantly, the local CPV in some regions of the Dalitz plots can reach the order of $10\%$, or be even larger. Considering the predicted results and the experimental data samples, we strong suggest to measure the CPV of ${\Lambda }_b^0\to (p{\pi }^{+}{\pi }^{-})K^{-}$, which has a large possibility to achieve the first observation of CPV in the baryon system.

10 pages, 5 figures, 1 table. Updated to match the published version

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Cited by in corpus (6)

• Study of $\itΛ_{\it{b}}^\rm{0}$ and $\itΞ_{\it{b}}^\rm{0}$ decays to $\Lambda h^{+}{h}^{{}^{\prime }-}$ and evidence for $CP$ violation in $\itΛ_{\it{b}}^\rm{0}\to\itΛ K^+K^-$ decays
• Final-state rescattering mechanism in bottom-baryon decays
• Implications of recent LHCb data on CPV in b-baryon four body decays
• Topological amplitudes of bottom baryon decays in the $SU(3{)}_F$ limit
• Prospects for $P$ and $CP$ violation in ${\Lambda }_c^{+}$ decays with polarized beam at Super Tau-Charm Facility
• Search for the lepton number violation decay $\omega \to {\pi }^{+}{\pi }^{+}{e}^{-}{e}^{-}+c.c.$