Upstream ionization instability associated with a current-free double layer.

@article{Aanesland2006UpstreamII,
  title={Upstream ionization instability associated with a current-free double layer.},
  author={Ane Aanesland and Christine Charles and Marcel Lieberman and Rod W. Boswell},
  journal={Physical review letters},
  year={2006},
  volume={97 7},
  pages={075003}
}
A low frequency instability has been observed using various electrostatic probes in a low-pressure expanding helicon plasma. The instability is associated with the presence of a current-free double layer (DL). The frequency of the instability increases linearly with the potential drop of the DL, and simultaneous measurements show their coexistence. A theory for an upstream ionization instability has been developed, which shows that electrons accelerated through the DL increase the ionization… CONTINUE READING