The reflection and transmission of a plane ion-acoustic soliton from a steep density gradient in front of a sheath have been investigated experimentally in an ion pulse beam system. An incident pulse tunnels through the space-charge sheath area without time delay and separates into three pulses at the plasma-sheath boundary. These pulses consist of a reflected and two transmitted pulses. One of them is a pulse of a fast ion-beam mode, while the others are ion-acoustic waves. The model for interpreting the phenomena is discussed.

• Received 10 December 1993

DOI:https://doi.org/10.1103/PhysRevE.49.4442