Theoretical density diagnostics using the ratios R₁–R₃ for the non-Maxwellian κ-distributions. Maxwellian ratios are shown in black, while ratios for κ = 5 and 2 are shown in green and red, respectively. Three lines for each distribution are shown, with the full lines showing the ratio at the respective peak of the relative ion abundance, while the dotted and dashed ones correspond to temperatures where the relative ion abundance is 0.01 of the maximum value.