Aanesland A, Charles C, Lieberman M A, Boswell R W
SP3, Research School of Physical Sciences and Engineering, The Australian National University, Australian Capital Territory 0200, Australia.
Phys Rev Lett. 2006 Aug 18;97(7):075003. doi: 10.1103/PhysRevLett.97.075003.
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 upstream and are responsible for the observed instability. The theory is in good agreement with the experimental results.
在低压膨胀螺旋波等离子体中，使用各种静电探针观测到了一种低频不稳定性。该不稳定性与无电流双层（DL）的存在有关。不稳定性的频率随DL的电位降线性增加，同时测量表明它们共存。已经发展了一种关于上游电离不稳定性的理论，该理论表明通过DL加速的电子增加了上游的电离，并导致了观测到的不稳定性。该理论与实验结果吻合良好。
