Electron Density Fluctuation in a Dusty Plasma

The expressions of electron density fluctuation produced by dust particles in a dusty plasma are derived.It is shown that the fluctuation comes from three different sources.The first source is the thermal motion of the dust particles,which is of a fluctuation power spectrum proportional to ndZ^2.The second source is the charge change of the dust particles,which is of a power spectrum proportional to nd^2Z%3.The third source is the eigenmode oscillation of the dust particles,which is of fluctuation power spectrum proportional to √nd.The powerful electron density fluctuation exists in a dusty plasma due to the fact that the dust particles ar highly charged.The results may explain the strong electromagnetic scattering by a space dust layer in the Earth‘s mesosphere.