Amplitude analysis of the decay $\overline{B}^0 \to K_{S}^0 \pi^+ \pi^-$ and first observation of the CP asymmetry in $\overline{B}^0 \to K^{*}(892)^- \pi^+$ : arXiv

The time-integrated untagged Dalitz plot of the three-body hadronic charmless decay B¯ 0 → K0 Sπþπ− is studied using a pp collision data sample recorded with the LHCb detector, corresponding to an integrated luminosity of 3.0 fb−1. The decay amplitude is described with an isobar model. Relative contributions of the isobar amplitudes to the B¯ 0 → K0 Sπþπ− decay branching fraction and CP asymmetries of the flavor-specific amplitudes are measured. The CP asymmetry between the conjugate B¯ 0 → K*892Þ−πþ and B0 → K*(892()-π− decay rates is determined to be −0.308 0.062.