Absorption line profiles for the quasar 3C298, plotted against velocity in km s⁻¹ in the regions around N III and NIII*. The normalized flux is shown on the y-axis, and the absorption lines of Lyϵ, C III, N III, and NIII* are labeled. The dashed green line shows the local continuum model, and the dashed red and dotted blue lines show the ±5% uncertainties. The integration range for N III and NIII* is also shown with blue and red arrows, respectively.