. (A) $\psi_{\mathrm{V}}$ distribution for correlated $\mathrm{e}^{+}\mathrm{e}^{-}$ pairs originating from different dielectron sources. (B) Correlation between $\psi_{\mathrm{V}}$ and $m_{\mathrm{ee}}$ for electron-positron pairs produced by photon conversion in the detector material. Their tracks have passed the single-track conversion rejection. The regions used to select the conversion pair candidates are indicated by the red boxes.