We present a Dalitz-plot analysis of charmless B± decays to the final state π±π±π using 210fb-1 of data recorded by the BABAR experiment at s=10.58GeV. We measure the branching fractions B(B±→π±π±π)=(16.2±1.2±0.9) ×10-6 and B(B±→ρ0(770)π±)=(8.8±1. 0±0.6-0.7+0.1)×10-6. Measurements of branching fractions for the quasi-two-body decays B±→ρ0(1450)π±, B±→f0(980)π± and B±→f2(1270)π± are also presented. We observe no charge asymmetries for the above modes, and there is no evidence for the decays B±→χc0π±, B±→f0(1370)π± and B±→σπ±. © 2005 The American Physical Society.

Branching fraction and asymmetry measurements of charmless B+→K*+h1+h2- (where h1,2=K, π) decays are presented, using a data sample of 232×106 Υ(4S)→BB̄ decays collected with the BABAR detector at the SLAC PEP-II asymmetric-energy B factory. Using a maximum likelihood fit, the following branching fraction results were obtained: B(B+→K*+K+K-)=(36.2±3.3±3.6)×10-6 and B(B+→K*+π+π-)=(75.3±6.0±8.1)×10-6. Upper limits were set for B(B+→K*+π+K-)<11.8×10-6 and B(B+→K*+K+π-)<6.1×10-6 at 90% confidence level. The charge asymmetries for the decays B+→K*+K+K- and B+→ K*+π+π- were measured to be AK*KK=0.11±0.08±0.03 and AK*ππ=0.07±0.07±0.04, respectively. The first error quoted on branching fraction and asymmetry measurements is statistical and the second systematic. © 2006 The American Physical Society.

The branching fraction of the τ-→3h-2h+ντ decay (h=π,K) is measured with the BABAR detector to be (8.56±0.05±0.42) ×10-4, where the first error is statistical and the second systematic. The observed structure of this decay is significantly different from the phase space prediction, with the ρ resonance playing a strong role. The decay τ-→f1(1285)π-ντ, with the f1(1285) meson decaying to four charged pions, is observed and the branching fraction is measured to be (3.9±0.7±0.5)×10-4. © 2005 The American Physical Society.

We present a measurement of the cross section of the process e(+)e(-)-->pi(+)pi(-)psi(2S) from threshold up to 8 GeV center-of-mass energy using events containing initial-state radiation, produced at the SLAC PEP-II e(+)e(-) storage rings. The study is based on 298 fb(-1) of data recorded with the BABAR detector. A structure is observed in the cross section not far above threshold, near 4.32 GeV. We also investigate the compatibility of this structure with the Y(4260) previously reported by this experiment.

We report the observation of the decay B-→Dπ+π-π0K-, where Dπ+π-π0 indicates a neutral D meson detected in the final state π+π-π0, excluding KS0π0. This doubly Cabibbo-suppressed decay chain can be used to measure the CKM phase γ. Using about 229×106 e+e-→BB̄ events recorded by the BABAR experiment at the PEP-II e+e- storage ring, we measure the branching fraction B(B-→Dπ+π-π0K-)= (5.5±1.0(stat.)±0.7(syst.))×10-6 and the decay rate asymmetry A(B-→Dπ+π-π0K-)=-0.02±0.16(stat.)±0. 03(syst.) for the full decay chain. © 2005 The American Physical Society.

A Dalitz plot analysis of approximately 12500 D0 events reconstructed in the hadronic decay D0→K̄0K+K- is presented. This analysis is based on a data sample of 91.5fb-1 collected with the BABAR detector at the PEP-II asymmetric-energy e+e- storage rings at SLAC running at center-of-mass energies on and 40 MeV below the Υ(4S) resonance. The events are selected from e+e-→cc̄ annihilations using the decay D*+→D0π+. The following ratio of branching fractions has been obtained: BR= Γ(D0→K̄0K+K-)Γ(D0→K̄0π+π-)=(15.8±0. 1(stat.)±0.5(syst.))×10-2. Estimates of fractions and phases for resonant and nonresonant contributions to the Dalitz plot are also presented. The a0(980)→K̄K projection has been extracted with little background. A search for CP asymmetries on the Dalitz plot has been performed. © 2005 The American Physical Society.