Reply to Comment by Nishimura Et Al.

Nishimura et al. (2010,, 2011,, 2013,, and in their comment, hereafter called N18) have suggested that chorus waves interact with equatorial electrons to produce pulsating auroras. We agree that chorus can scatter electrons >10 keV, as do Time Domain Structures (TDSs). Lower-energy electrons occurring in pulsating auroras cannot be produced by chorus, but such electrons are scattered and accelerated by TDS. TDSs often occur with chorus and have power in their spectra at chorus frequencies. Thus, the absence of power at low frequencies is not evidence that TDSs are absent, as an example shows. Through examination of equatorial electric field waveforms and electron pitch angle distributions measured on the Time History of Events and Macroscale Interactions during Substorms satellites (in place of examining field and particle spectra, as done by Nishimura et al.), we show that chorus cannot produce the field-aligned electrons associated with pulsating auroras in the Nishimura et al. (2010, events, but TDSs can. Equatorial field-aligned electron distributions associated with pulsating auroras and created by TDS in the absence of chorus or any other wave at the equator are also shown.
Year of Publication
Journal of Geophysical Research: Space Physics
Date Published