Top panel: parameter ξ_CIV behavior as a function of viewing angle as a function of θ for a “thin” emitting region with κ = 0.1, for different 𝒬 values (0.4, 1.6, 4.0, 12.0; black lines). Red line: ξ_CIV behavior for a thick emitting region κ = 0.5, for the same 𝒬 values. Bottom panel: as in top panel but for κ = 0.1, with 𝒬 = 12. The thin lines are the values for Hβ (black) and C IVλ1549 (blue). See text for more details. The thick line is their ratio (also shown in the top panel).