Fig. 3
From: A review of unusual VLF bursty-patches observed in Northern Finland for Earth, Planets and Space
Example of long lasting hiss-like VLF bursty-patches at KAN. Power spectrum density at KAN on 03 April 2020 from a 06:30 to 10:30 UT (08:00–11:30 MLT) and from b 07:55 to 07:59 UT, between 0 and 10 kHz. Dashed and dotted horizontal white lines show, respectively, the local equatorial 0.5 fce and fce for the L-shell of KAN. Short VLF bursty-patches are observed from ~ 07:00 to 08:00 UT. A long-lasting hiss-like VLF bursty-patch is observed at 5–7 kHz for almost the entire 4 h