Opposite-sign dielectron invariant mass distributions for the \pt-intervals used for this analysis. The signal plus total background (blue), the combinatorial background (red), and the correlated background (green), evaluated as described in the text, are shown separately in each panel The $\chi^2/{\rm ndf}$ values of the signal template plus the total background function are also reported along with the raw yields in the range $2.92 < m_{\rm e^+e^-} < 3.16$ GeV/$c^2$.