Observation of B meson decaying to a neutral strange kaon pion-antipion, and B meson decaying to kaon*(892) pion-antipion and measurement of the charge asymmetry in B meson decaying to kaon*(892) pion-antipion

We report on a search for charmless hadronic B decays to the three-body final states $K0S$h±π∓, K±h∓π 0, and $K0S$h±π0 ( h± denotes a charged pion or kaon), using 9.12 fb−1 of integrated luminosity produced at $s$ = 10.58 GeV and collected with the CLEO detector. We observe the decay B → K0/K¯ 0π+π− with a branching fraction ($50+10-9$ ± 7) × 10−6 and the decay B → K*(892)±π ∓ with a branching fraction ($16+6-5$ ± 2) × 10−6, where the uncertainties are statistical and systematic, respectively. Both branching fractions are averages over CP-conjugate states. We also search for a CP-violating asymmetry in the decay B → K*(892)±π∓. We find $ACP$(B → K*(892)± π∓) = $0.26+0.33+0.10-0.34-0.08$, giving an allowed interval of [−0.31, 0.78] at the 90% confidence level. These measurements are used to constrain fundamental parameters of the Standard Model.