Observation of several sources of CP violation in B+→π+ π+ π- decays

Abstract

Observations are reported of different sources of CP violation from an amplitude analysis of B[superscript +] → π[superscript +] π[superscript +] π[superscript -] decays, based on a data sample corresponding to an integrated luminosity of 3 fb-¹ of pp collisions recorded with the LHCb detector. A large CP asymmetry is observed in the decay amplitude involving the tensor f[subscript 2](1270) resonance, and in addition significant CP violation is found in the π[superscript +] π[superscript -] S wave at low invariant mass. The presence of CP violation related to interference between the π[superscript +] π[superscript -] S wave and the P wave B[superscript +] → ρ(770)[superscript 0] π[superscript +] amplitude is also established; this causes large local asymmetries but cancels when integrated over the phase space of the decay. The results provide both qualitative and quantitative new insights into CP -violation effects in hadronic B decays.