Laboratory observations of Farley-Buneman instability

An experiment simulating certain characteristics of the equatorial electrojet plasma (viz. Vsub(en)<<Ωsub(e), Vsub(in)>>Ωsub(i)) is described. Instabilities are observed when electrons stream past ions with a velocity exceeding the ion acoustic speed. The observed phase velocities and frequencies agree with the results of Farley-Buneman instability theory, modified to take account of finite k(parallel). The instability spectrum and measurements of cross-field particle transport are also discussed. (Auth.)