Measurement of the $e^+e^- \to ηπ^+π^-$ cross section in the center-of-mass energy range 1.22--2.00 GeV with the SND detector at the VEPP-2000 collider

Abstract

In the experiment with the SND detector at the VEPP-2000 $e^+e^-$ collider the cross section for the process $e^+e^-\toηπ^+π^-$ 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 $e^+e^-\toηπ^+π^-$ cross section has been fitted with the vector-meson dominance model. From this fit the product of the branching fractions $B(ρ(1450)\toηπ^+π^-)B(ρ(1450)\to e^+e^-)$ has been extracted and compared with the same products for $ρ(1450)\toωπ^0$ and $ρ(1450)\toπ^+π^-$ decays. The obtained cross section data have been also used to test the conservation of vector current hypothesis.

9 pages, 7 figures