Figure 6.

The positions of the meridional and equatorial planes on the image of the calculated intensity of a helical wire six full pitches long at Ψ = 0, from which the intensity profiles shown in Fig. 7 ▸ are extracted. The positions of the meridional planes M ₀ and M ₁ are at R = 0 and 0.0463 Å⁻¹, respectively, and the equatorial plane is at Z = 0. The profiles from Fig. 5 ▸ are shown in Fig. 7 ▸.