Propagation of Plasma Waves across a Density Discontinuity

The linearized plasma equations and the boundary conditions to be satisfied across a surface of density discontinuity are considered. It is shown that an incident longitudinal plasma wave generates reflected and transmitted transverse plasma waves, as well as reflected and transmitted longitudinal waves. The inverse process also occurs. The transverse waves are generated only when the longitudinal wave is almost normally incident; in the inverse process, the generated longitudinal waves are propagated normal to the boundary.