School of Physics, University of Sydney, Sydney, New South Wales 2006, Australia.
Phys Rev Lett. 2013 May 3;110(18):185001. doi: 10.1103/PhysRevLett.110.185001. Epub 2013 Apr 30.
The kinematics of the electrostatic (ES) decay of a Langmuir wave into a Langmuir wave and an ion sound wave are generalized to a weakly magnetized plasma. Unlike the unmagnetized case, ES decay in a magnetized plasma is always kinematically permitted and can produce daughter Langmuir waves with very small wave numbers, which we demonstrate by quasilinear simulations. The simulations further show that ES decay in magnetized plasmas is consistent with STEREO spacecraft observations of transversely polarized Langmuir waves in the solar wind.
静电磁（ES）衰减的运动学将Langmuir 波分解为 Langmuir 波和离子声波，推广到弱磁化等离子体中。与非磁化情况不同，磁化等离子体中的 ES 衰减在运动学上总是允许的，并能产生波数非常小的子 Langmuir 波，我们通过准线性模拟证明了这一点。模拟还表明，磁化等离子体中的 ES 衰减与 STEREO 航天器在太阳风中观测到的横向极化 Langmuir 波一致。
