Measurement of the e + e − → ηπ+π− cross section in the \( \sqrt s \) = 1.04–1.38-GeV energy range with a spherical neutral detector at the VEPP-2M collider

The e + e − → ηπ+π− cross section in the η → 2γ channel has been measured in the \( \sqrt s \) = 1.04- to 1.38-GeV energy range. The data with a total integrated luminosity of 9.05 pb−1 were collected on a spherical neutral detector at the VEPP-2M collider. The results are consistent with the BaBar and CMD2 data and have a higher statistical accuracy.