Large-amplitude magnetic pulses downstream of the Jovian bow shock: Ulysses observations

Abstract

We report the first finding of large-amplitude magnetic pulses in the Jovian magnetosheath. The pulses are highly compressional with Δ| B|/| B| ranging from 0.5 to 2.0. Each pulse contains a full 360° phase rotation. These solitary waves are propagating at an angle nearly orthogonal to the ambient magnetic field ( θ_kB > 83°). A determination of the sense of rotation about B₀ therefore cannot be made. The waves are elliptically polarized. The scale size of the pulses is ∼8-17 proton gyroradii in the plasma frame. We compare these Jovian pulses with similar phenomena occurring at Earth (short large-amplitude magnetic structures: SLAMS) and at comet Giacobini-Zinner.