On the excitation of low-frequency instabilities in magnetized plasmas

We propose a new phenomenological model, based on self-organization phenomena, which is able to explain the role of complex space charge configurations in the excitation of low frequency instabilities in a Q machine. Our model can also explain the recently observed interaction between them. We assume that for instabilities nonlinear space charge accumulations are relevant. These are created due to the different locations where the neutrals excitation and ionization cross section reach their respective maxima in a region where a gradient of the electron kinetic energy is present. (author)