Measurement of the e+e\u2212 \u2192 \u03c0+\u03c0\u2212 process cross section with the SND detector at the VEPP-2000 collider in the energy region 0.525 < sqrt{s} < 0.883 GeV

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The cross section of the process e+e− → π+π− has been measured in the Spherical Neutral Detector (SND) experiment at the VEPP-2000 e+e− collider VEPP-2000 in the energy region 525 < sqrt{s} < 883 MeV. The measurement is based on data with an integrated luminosity of about 4.6 pb−1. The systematic uncertainty of the cross section determination is 0.8% at sqrt{s} > 0.600 GeV. The ρ meson parameters are obtained as mρ = 775.3 ± 0.5 ± 0.6 MeV, Γρ = 145.6 ± 0.6 ± 0.8 MeV, Bρ→e+e− × Bρ→π+π− = (4.89 ± 0.02 ± 0.04) × 10−5, and the parameters of the e+e− → ω → π+π− process, suppressed by G-parity, as Bω→e+e− × Bω→π+π− = (1.32 ± 0.06 ± 0.02) × 10−6 and and ϕρω = 110.7 ± 1.5 ± 1.0 degrees.