Distribution of Δϕ separation of all hemispheric (blue), northern hemisphere (green), and southern hemisphere (orange) flare pairs with w ≤ 1.5 hour. Panels a–c consider the whole cycle 24, the rising phase and the decaying phase, respectively. The time intervals are shown as vertical black dashed lines in Figure 2. The histograms are normalized so that the combined global distribution of both hemispheres integrates to unity. The black solid lines indicate fits of Equation (3) and the gray area indicates the $\sqrt{N}$ counting error.