Evidence for correlated double layers, bipolar structures, and very-low-frequency saucer generation in the auroral ionosphere

Recent observations by the Fast Auroral SnapshoT satellite have provided high-time-resolution measurements of three interrelated phenomena in the downward current region of the auroral ionosphere: Intense parallel electric fields (double layers) localized to tens of Debye lengths; drifting localized bipolar field structures interpreted in terms of electron phase-space holes; and intense quasi-electrostatic whistler emissions (very-low-frequency saucers) originating on the same field lines as the bipolar structures. Numerical simulations and theoretical modeling suggest how these observations may be related