论文标题
在存在不平衡的情况下，直接动力学的alfvén波能量级联
Direct kinetic Alfvén wave energy cascade in the presence of imbalance
论文作者
论文摘要
用于动力学alfvén波的两场hamiltonian陀螺仪模型保留离子有限拉莫尔半径校正和平行磁场波动，用于研究从MHD到亚离子尺度的直接湍流级联。对于中等能量不平衡和足够弱的磁波动，横向磁场的光谱和最伟大的波浪的光谱在离子尺度附近显示一个陡峭的过渡区，而平行转移（因此平行耗散）仍然很弱。在这种制度中，广义交叉螺旋性的垂直通量显示出超过离子量表的显着衰减，而垂直能量通量几乎保持恒定。一个现象学模型表明，在存在螺旋屏障的情况下，在亚离子量表处存在的综合波之间的相互作用在过渡区的发展中起着核心作用。
A two-field Hamiltonian gyrofluid model for kinetic Alfvén waves retaining ion finite Larmor radius corrections and parallel magnetic field fluctuations is used to study direct turbulent cascades from the MHD to the sub-ion scales. For moderate energy imbalance and weak enough magnetic fluctuations, the spectrum of the transverse magnetic field and that of the most energetic wave display a steep transition zone near the ion scale, while the parallel transfer (and thus the parallel dissipation) remains weak. In this regime, the perpendicular flux of generalized cross helicity displays a significant decay past the ion scale, while the perpendicular energy flux remains almost constant. A phenomenological model suggests that the interactions between co-propagative waves present at the sub-ion scales can play a central role in the development of a transition zone in the presence of a helicity barrier.
