Fig. 8

Coherence (\(\gamma ^2\)) spectra of the H (bold lines) and D (thin lines) components for the event shown in Figs. 6 and 7. \(\gamma ^2(f)\) for station pairs located along MM100 (MLT \(\approx 3\)) are shown at top and bottom left panels (H component is shown by solid magenta lines). \(\gamma ^2(f)\) for station pairs formed from MM100 stations located at nightside and MM185/MM210 stations located at dayside are given in the central column and at the central panel of the left column. Blue lines correspond to station pairs with approximately the same L. Two panels in the right column show \(\gamma ^2\) spectra for station pairs located in the morning MLT sector