Te. Sheridan, SOME PROPERTIES OF LARGE-AMPLITUDE, NEGATIVE-POTENTIAL SOLITARY WAVESIN A 3-COMPONENT PLASMA, Journal of Plasma Physics, 60, 1998, pp. 17-28
Large-amplitude, negative-potential solitary waves in a plasma contain
ing positive and negative, cold, collisionless ions and isothermal ele
ctrons are studied computationally and analytically. When their amplit
ude and speed are large, both speed and width are proportional to the
square root of amplitude. That is, amplitude is proportional to speed
squared, while width increases directly with speed. Approximate expres
sions relating these quantities are derived.