Characteristics of Solitary Waves and Weak Double Layers in the Magnetospheric Plasma

The wave experiment of the Viking satellite frequently detected dynamic small-scale (\ensuremath{\simeq} 100 m), large-amplitude, rarefactive ($|\frac{\ensuremath{\Delta}n}{n}|\ensuremath{\lesssim}50%$) solitary waves of negative potential ($|\ensuremath{\varphi}|\ensuremath{\lesssim}2$ V) moving upwards along the magnetic field lines ($\ensuremath{\upsilon}=5 \mathrm{to} >50$ km/s). The structures, which resemble ion holes, often have an upward-directed net potential drop (\ensuremath{\lesssim} 1 V) and are then interpreted as weak double layers.