Evolution of the X-ray profile with altitude and extension of the emission region for χ = 45° and ζ = 44°. The legend shows the lower and upper radii, {r_in/r_L, r_out/r_L}, respectively denoted by r_in and r_out, for the region of the separatrix emitting in X-ray. The upper rows show the individual light curves that are progressively added together in the lower rows to the point where all are stacked to get only one possible light curve, shown by the lowest row.