Study of the $e^+e^-\to\eta\gamma$ process with SND detector at the VEPP-2M $e^+e^-$ collider

TL;DR

This study measures the cross section of the process $e^+e^- o ext{eta} ext{gamma}$ across a range of energies using the SND detector, confirming the vector meson dominance model and providing precise decay probabilities.

Contribution

First measurement of the $e^+e^- o ext{eta} ext{gamma}$ cross section in the specified energy range with detailed resonance contributions and improved decay probability measurements.

Findings

Cross section well described by vector meson dominance model.

Measured decay probabilities with improved accuracy.

Results agree with previous measurements.

Abstract

In experiment with the SND detector at VEPP-2M $e^+e^-$ collider the $e^+e^-\to\eta\gamma$ cross section was measured in the energy range $E$=0.60--1.38 GeV with the integrated luminosity of 27.8 pb$^{-1}$. The measured cross section is well described by the vector meson dominance model with contributions from the $\rho(770)$, $\omega(783)$, $\phi(1020)$, $\rho^{\prime}(1465)$ resonances and agrees with results of previous measurements. The decay probabilities $\BR(\phi\to\eta\gamma)$, $\BR(\omega\to\eta\gamma)$ and $\BR(\rho\to\eta\gamma)$ were measured with the accuracies better than or comparable to the world averages.