Experimental observation of multiple double Layers structures in Plasma-part II: nonconcentric multiple double Layers

In certain experimental conditions, in front of a positively biased electrode immersed into a diffusion plasma, a concentric multiple double layers structure can appear. If the electrode is large or asymmetric (one dimension is larger than the others), this structure appears nonconcentrically, as many spherical luminous structures attached to the electrode. Each of these structure consists of a positive nucleus (an ion-rich plasma) bordered by an electrical double layer. The structures are almost equally distributed on the electrode because of the negative external shell of the double layer.