Slow electron phase space holes: Magnetotail observations

Abstract

We report multispacecraft observations of slow electrostatic solitary waves in the plasma sheet boundary layer. The electrostatic solitary waves are embedded in a region with field-aligned electron flows and are interpreted as electron phase space holes. We make unambiguous velocity and length estimates of the electron holes, v EH ∼500 km/s and l || ∼2-4λ De, where l || is the parallel half width. We do not detect any magnetic signature of the holes. The electrostatic potentials of the holes are of the order eφ/k B T e ∼10%, indicating that they can affect electron motion and further couple the electron and ion dynamics. Key Points Cross-spacecraft measurements of slow electron holes Potential strength and phase velocity of slow electron holes Slow electron holes indicate coupling between ions and electrons