Title: Measurement of the $e^+e^-\toηγ$ cross section near the $φ(1020)$ resonance with the SND detector Show Chinese title

Title: 在 SND 探测器上测量接近$φ(1020)$共振的$e^+e^-\toηγ$截面

Abstract: In the experiment with the SND detector at the VEPP-2000 $e^+e^-$ collider, the $e^+e^-\to\eta\gamma$ cross section is measured in the energy range $E = 980 - 1060$ MeV. The measurement is carried out in the $\eta\to 2\gamma$ decay mode. Data with an integrated luminosity of 73 pb$^{-1}$ collected in 2018 and 2024 are used in the analysis. The measured cross section is the most accurate to date and is higher compared to other measurements. From the fit to the cross section data with the vector meson dominance model, the value of the product of the branching fractions $B(\phi\to e^+e^-)B(\phi\to \eta\gamma)$ has been obtained. Show Chinese abstract

Abstract: 在SND探测器在VEPP-2000$e^+e^-$对撞机上的实验中，在能量范围$E = 980 - 1060$MeV内测量了$e^+e^-\to\eta\gamma$截面。 该测量是在$\eta\to 2\gamma$衰变模式下进行的。 使用了在2018年和2024年收集的积分亮度为73 pb$^{-1}$的数据进行分析。 测量得到的截面是迄今为止最精确的，并且与其他测量结果相比更高。 通过将截面数据与矢量介子主导模型进行拟合，得到了分支比乘积$B(\phi\to e^+e^-)B(\phi\to \eta\gamma)$的值。