Parameters of the Fe Kα line plotted against the primary flux in the 3–10 keV band. The red square corresponds to the 2004 XMM–Newton observation. Panel A: line flux in units of photons cm⁻² s⁻¹. Panel B: line equivalent width in units of eV. Error bars denote the 1σ uncertainty. The blue solid lines represent the mean value for each parameter during the campaign, while the blue dashed lines represent the standard deviation.