Observation of ion-acoustic shock waves undergoing Landau damping

Numerical results of a modified Korteweg–de Vries equation with an integral term which describes Landau damping have been compared with the experimental findings. In the linear regime, the wave damping rate is proportional to wave number, which conforms to a kinetic dispersion relation. Transition of an oscillatory ion-acoustic shocklike structure into a monotonic shock has been observed when Landau damping is introduced by mixing H 2 ions with an Ar plasma. Quenching of the oscillatory stucture behind the wave front is identified as a dissipation charateristic governed by the strength of Landau damping.