Fig. 4.

Uncertainty from various sources on $(1/\mathit{\sigma })\mathrm{d}\mathit{\sigma }/\mathrm{d}{\mathit{\varphi }}_{\mathit{\eta }}^{\ast }$ (top) and $(1/\mathit{\sigma })\mathrm{d}\mathit{\sigma }/\mathrm{d}{p}_{\mathrm{T}}^{\ell \ell }$ (bottom) for events with $66\mathrm{GeV}<m_{\ell \ell }<116\mathrm{GeV}$ and $|y_{\ell \ell }|<2.4$. Left Electron-pair channel at dressed level. Right Muon-pair channel at bare level