Fig. 3.

Impact of non-resonant backgrounds on the measurement of $\sum p_{\mathrm{T}}$ in the bin $30$ GeV $<\mathrm{\Sigma }{p}_{\mathrm{T}}<32$ GeV and in the toward region for $30$ GeV $<p_{\mathrm{T}}^{\mathrm{Z}}<35$ GeV. This is shown separately for the electron and muon channels as a function of the window applied to the dilepton mass $|m_{\mathrm{ll}}-M_{\mathrm{Z}}|<\mathrm{\Delta }{m}_{\mathrm{ll}}$. The unfolded value for each channel is normalised to the corrected combined result. The statistical uncertainties at individual $\mathrm{\Delta }{m}_{\mathrm{ll}}$ points are strongly correlated within each channel. The uncertainty range of the linear fit is shown by hatched bands for each channel. This includes the statistical and systematic uncertainties from the fit itself, as well as the relevant correlations. The vertical line at $\mathrm{\Delta }{m}_{\ell \ell }=0$ marks the points to which the extrapolations are made