Observed velocity profiles of the H-like resonance lines of Si XIV, Mg XII, Ne X, and O VIII (shaded blue) compared with simple emission models. Solid gray profiles represent an unabsorbed thin spherical shell with an expansion velocity of 1200 km s⁻¹; dashed red profiles correspond to a spherical cap with an opening angle of 50° inclined toward the observer at 5° relative to the plane of the sky and expanding with a velocity of 2000 km s⁻¹; solid red curves correspond to the same model subject to intrinsic absorption interior to the sphere with an equivalent hydrogen column density of N_H = 5 × 10²¹ cm⁻².