Vranjes J, Poedts S
Centre for Plasma Astrophysics, Celestijnenlaan 200B, 3001 Leuven, Belgium.
Phys Rev E Stat Nonlin Soft Matter Phys. 2010 Aug;82(2 Pt 2):026411. doi: 10.1103/PhysRevE.82.026411. Epub 2010 Aug 31.
A purely kinetic instability of the dust acoustic mode in inhomogeneous plasmas is discussed. In the presence of a magnetic field, electrons and ions may be magnetized while at the same time dust grains may remain unmagnetized. Although the dynamics of the light species is strongly affected by the magnetic field, the dust acoustic mode may still propagate in practically any direction. The inhomogeneity implies a source of free energy for an instability that develops through the diamagnetic drift effects of the magnetized species. It is shown that this may be a powerful mechanism for the excitation of dust acoustic waves. The analysis presented in the work is also directly applicable to plasmas containing both positive and negative ions and electrons, provided that at least one of the two ion species is unmagnetized.
讨论了非均匀等离子体中尘埃声模的纯动力学不稳定性。在存在磁场的情况下，电子和离子可能被磁化，而与此同时尘埃颗粒可能仍未被磁化。尽管轻粒子的动力学受到磁场的强烈影响，但尘埃声模仍可在几乎任何方向传播。这种不均匀性意味着一种自由能来源，可引发通过磁化粒子的抗磁漂移效应发展起来的不稳定性。结果表明，这可能是激发尘埃声波的一种强大机制。该工作中给出的分析也直接适用于包含正离子、负离子和电子的等离子体，前提是两种离子物种中至少有一种未被磁化。
