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The process e + e − → nn has been studied at the VEPP-2000 e + e − collider with the SND detector in the energy range from threshold up to 2 GeV. As a result of the experiment, the e + e − → nn cross section and effective neutron form factor have been measured.

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In the experiment with the SND detector at the VEPP-2000 e + e − collider the cross section for the process e + e − → ηπ + π − has been measured in the center-of-mass energy range from 1.22 to 2.00 GeV. Obtained results are in agreement with previous measurements and have better accuracy. The energy dependence of the e + e − → ηπ + π − cross section has been fitted with the vector-meson dominance model. From this fit the product of the branching fractions B(ρ(1450) → ηπ + π − )B(ρ(1450) → e + e − ) has been extracted and compared with the same products for ρ(1450) → ωπ 0 and ρ(1450) → π + π − decays. The obtained cross section data have been also used to test the conservation of vector current hypothesis.

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 <$$ \sqrt{s} $$ 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 $$ \sqrt{s} $$ 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.