CP violation in multibody decays of beauty baryons

Abstract

Beauty baryons are being observed in large numbers in the LHCb detector. The rich kinematic distributions of their multibody decays are therefore becoming accessible and provide us with new opportunities to search for CP violation. We analyse the angular distributions of some three- and four-body decays of spin-$1/2$ baryons using the Jacob-Wick helicity formalism. The asymmetries that provide access to small differences of CP-odd phases between decay amplitudes of identical CP-even phases are notably discussed. The understanding gained on processes featuring specific resonant intermediate states allows us to establish which asymmetries are relevant for what purpose. It is for instance shown that some CP-odd angular asymmetries measured by the LHCb collaboration in the ${\Lambda }_b\to \Lambda \phi \to p\pi K^{+}{K}^{-}$ decay are expected to vanish identically.

2 figures, 16 tables, minor comments and references added in v2 (published version)

References in corpus (4)

• Photon polarization from helicity suppression in radiative decays of polarized Lambda_b to spin-3/2 baryons
• Study of CP violation in ${\Lambda }_c^{+}$ decay
• Photon helicity in Lambda_b --> p K gamma decays
• Testing CP and Time Reversal Symmetries with ${\Lambda }_b\to \Lambda V(1-)$ Decays

Cited by in corpus (8)

• Direct CP violation in beauty and charm hadron decays
• Estimates of exchange topological contributions and $CP$-violating observables in ${\Lambda }_b\to \Lambda \varphi$ decay
• Analysis of angular distribution asymmetries and the associated $CP$ asymmetries in three-body decays of bottom baryons
• Final-state rescattering mechanism in bottom-baryon decays
• Searching for $CP$ violation through two-dimensional angular distributions in four-body decays of bottom and charmed baryons
• Topological amplitudes of bottom baryon decays in the $SU(3{)}_F$ limit
• $CP$-violation and $U$-spin symmetry in four-body bottom baryon decays
• Search for $CP$ violation in $D_{(s)}^{+}\to K_S^0{K}^{-}{\pi }^{+}{\pi }^{+}$ decays using triple and quadruple products