Microwave-generated low-frequency plasma wave excited in the periphery of the evanescent layer

The observation of microwave-created low-frequency electrostatic waves from the evanescent layer in a pulsed plasma discharge and effects of a weak magnetic field on its propagation characteristics are reported. The creation of the electrostatic wave depends on the density variations along the direction of microwave propagation. It is observable when a part of the microwave is reflected and another part of it eventually gets absorbed in the resonance-absorption layers (ɷ=ɷpe) on two sides of the evanescent layer. The velocity of the wave is one order of magnitude higher than that of the ion-acoustic wave. Under the application of a very weak magnetic field (affecting only the electrons) perpendicular to the direction of propagation of both the excited plasma waves and the microwaves, the waves are still observable only with altered velocity and characteristics. At higher magnetic fields the electrostatic waves are completely subdued under a continuous instability independent of presence or absence of the ...