Fig. 1
From: ERG observations of drift echoes during a unique period of the satellite mission
a Locations of ERG, GOES-15, GOES-13 during the event initiating at ~ 22:30 UT on 5 April 2017. b The variations of IMF Bz. c, d, e AE, AL and ASY-H indices. f The magnitudes of magnetic field as indicated in the legend. g Bx and Bz (BIGRF subtracted from BMGF) in GSM coordinates h energy–time spectrograms from ERG HEP-L. Colors indicate electron differential fluxes (omni-flux data)