Soliton propagation, collision, and reflection at a sheath in a positive ion–negative ion plasma

Experiments on the propagation and collision of a Korteweg–deVries soliton in a positive ion–negative ion plasma are described. Both a one-dimensional overtaking collision and a two-dimensional resonant collision are examined. Soliton propagation into a steady-state plasma sheath created by an additional biased metal plate in such a plasma is large enough that the detailed soliton motion in the locally inhomogeneous plasma can be easily studied. A partial reflection and partial transmission of the soliton at a critical density within the sheath is observed and interpreted.