Fig. 19

Example stack plot of the HFA, OFA, and EFD observed on April 11, 2017. a electric wave spectrogram (HFA), b electric wave spectrogram (OFA-E), c magnetic wave spectrogram (OFA-B), d electric wave spectrogram (EFD), e DC electric field (EFD), f satellite potential (EFD), and g active periods of the PWE burst operation. The solid and dotted lines shown in panels a–c indicate the local electron cyclotron frequency (f_c) and half of f_c, respectively, derived from the DC magnetic field measured by the MGF. The shadows superposed on panels e and f represent the eclipse period that occurred from 07:53 to 08:34 UT along the trajectory of the Arase. “65 k”, “1 k”, and “WP” shown in panel g correspond to the time durations of “chorus burst”, “EMIC burst” and S-WPIA mode operations, respectively