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

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