Search for CP violation and a measurement of the relative branching fraction in D+→K-K+π+ decays

We report on a search for the CP asymmetry in the singly Cabibbo-suppressed decays D+→K-K+π+ and in the resonant decays D+→ϕπ+ and D+→K̅ *0K+ based on a data sample of 79.9  fb-1 recorded by the BABAR detector. We use the Cabibbo-favored Ds+→K-K+π+ branching fraction as normalization in the measurements to reduce systematic uncertainties. The CP asymmetries obtained are ACP(K-K+π±)=(1.4±1.0(stat)±0.8(syst))×10-2, ACP(ϕπ±)=(0.2±1.5(stat)±0.6(syst))×10-2, and ACP(K̅ *0K±)=(0.9±1.7(stat)±0.7(syst))×10-2. The relative branching fraction Γ(D+→K-K+π+)/Γ(D+→K-π+π+) is also measured and is found to be (10.7±0.1(stat)±0.2(syst))×10-2.