Measurement of the Branching Fraction, Polarization, andCPAsymmetry forB0→ρ+ρ−Decays, and Determination of the Cabibbo-Kobayashi-Maskawa Phaseϕ2

Measurement of the Branching Fraction, Polarization, andCPAsymmetry forB0→ρ+ρ−Decays, and Determination of the Cabibbo-Kobayashi-Maskawa Phaseϕ2