Time-dependent amplitude analysis of B^{0}→K_{S}^{0}π^{+}π^{-}

We perform a time-dependent amplitude analysis of B0→KS0π+π- decays to extract the CP violation parameters of f0(980)KS0 and ρ0(770)KS0 and the direct CP asymmetry of K*+(892)π-. The results are obtained from a data sample of (383±3)×106 BB̅ decays, collected with the BABAR detector at the PEP-II asymmetric–energy B factory at SLAC. We find two solutions, with an equivalent goodness-of-fit. Including systematic and Dalitz plot model uncertainties, the combined confidence interval for values of the CP parameter βeff in B0 decays to f0(980)KS0 is 18°<βeff<76° at 95% confidence level (C.L). CP conservation in B0 decays to f0(980)KS0 is excluded at 3.5 standard deviations including systematic uncertainties. For B0 decays to ρ0(770)KS0, the combined confidence interval is -9°<βeff<57° at 95% C.L. In decays to K*+(892)π- we measure the direct CP asymmetry to be ACP=-0.20±0.10±0.01±0.02. The measured phase difference (including B0B̅ 0 mixing) between decay amplitudes of B0→K*+(892)π- and B̅ 0→K*-(892)π+, excludes the interval -137°<ΔΦ(K*+(892)π-)<-5° at 95% C.L.