On some peculiarities of electric field pulse propagation in electron   Maxwellian plasma and its back response
  In the spirit of continued study of general plasma wave properties we investigated the boundary problem with the simplest form of electric field pulse at the edge x=0 of half-infinite uniform plasma slab with Maxwellian electron distribution function. In the case of longitudinal electric field pulse its traveling velocity is essentially other than in the case of harmonic waves; there is also no back response. In the case of transverse field pulse there takes place the bimodal propagation rate of the non-damping fast pulse signal and non-damping weak slow sign reversed pulse signals; some very weak response (echo) arises with a time delay in the near coordinate zone of formation of the asymptotical regime. 
V. N. Soshnikov