Snapshot of the initial background density (log scale) in the simulation domain. The full domain is plotted, ranging from photosphere to photosphere at the top and bottom boundaries, with the apex of the loop positioned at z = 0 Mm. The positions of field lines 1, 2, and 3 are also indicated and used for the discussion in the text. Contours for the plasma-β = 1 layer and transition region are denoted by the green and grey lines, respectively. The black dashed box outlines the sub-domain used for analysis at various points in the present study.