Topology of the expanded sunspot solution that includes the transition region and corona. Following E. Khomenko & M. Collados (2008), their Equations (6) and (7), the model is constructed using the following parameters: a = 2h, h = 3 Mm, B₀ = 20000 G, z₀ = 1 Mm, and η = 3.5. The white lines are magnetic field lines. The dashed lines with labels are the contours of the ratio of the sound speed and the Alfvén speed squared, ﹩({c}_{s}^{2}/{v}_{{\rm{A}}}^{2})﹩.