标题： 各向异性输运效应对稀薄等离子体的影响 显示英文标题

标题： The Anisotropic Transport Effects On The Dilute Plasmas

摘要： 我们研究了热、稀薄和不同旋转等离子体的线性稳定性分析，考虑了各向异性输运效应。在稀薄等离子体中，离子的回旋半径与其碰撞平均自由程相比很小。在这种情况下，沿磁力线的热量和动量输运变得重要。本文提出了一种新的线性不稳定性，在稀薄天体物理等离子体中可能比理想磁热不稳定性（MTI）和理想磁旋转不稳定性（MRI）更强大且更大。这种类型的等离子体被认为存在于星系团的星系间介质以及黑洞周围的辐射无效吸积流中。我们推导了这种不稳定性色散关系并得到了不稳定性条件。对于螺旋磁场几何结构，至少存在一个与温度梯度方向无关的不稳定模式。这种新不稳定性是由涡粘性与差速旋转耦合驱动的。因此我们称之为涡粘性修正磁旋转不稳定性（GvMRI）。我们研究了不稳定性如何依赖于温度梯度的符号和涡粘性的符号，以及热频率的大小和倾角的值。我们提供了获得结果的详细物理解释。由于不依赖于温度梯度方向，GvMRI不仅适用于吸积流和星系间介质，还适用于恒星日冕、吸积盘和多相星际介质中冷致密气体与热低密度等离子体之间的过渡区域。 显示英文摘要

摘要： We examine the linear stability analysis of a hot, dilute and differentially rotating plasma by considering anisotropic transport effects. In the dilute plasmas, the ion Larmor radius is small compared with its collisional mean free path. In this case, the transport of heat and momentum along the magnetic field lines become important. This paper presents a novel linear instability that may more powerful and greater than ideal magnetothermal instability (MTI) and ideal magnetorotational instability (MRI) in the dilute astrophysical plasmas. This type of plasma is believed to be found in the intracluster medium of galaxy clusters and radiatively ineffective accretion flows around black holes. We derive the dispersion relation of this instability and obtain the instability condition. There is at least one unstable mode that is independent of the temperature gradient direction for a helical magnetic field geometry. This novel instability is driven by the gyroviscosity coupled with differential rotation. Therefore we call it as gyroviscous modified magnetorotational instability (GvMRI). We examine how the instability depends on signs of the temperature gradient and the gyroviscosity, and also on the magnitude of the thermal frequency and on the values of the pitch angle. We provide a detailed physical interpretation of obtained results. The GvMRI is applicable not only to the accretion flows and intracluster medium but also to the transition region between cool dense gas and the hot low-density plasma in stellar coronae, accretion disks, and the multiphase interstellar medium because of being independent of the temperature gradient direction.