It is well known that magnetic fields constrain motions of charged particles, impeding the diffusion of charged particles perpendicular to magnetic field direction. This modification of transport processes is of vital importance for a wide variety of astrophysical processes including cosmic ray transport, transfer of heavy elements in the interstellar medium, star formation etc. Dealing with these processes one should keep in mind that in realistic astrophysical conditions magnetized fluids are turbulent. In this review we single out a single transport process, namely, heat transfer and consider how it occurs in the presence of the magnetized turbulence. We show that the ability of magnetic field lines to constantly change topology and connectivity is at the heart of the correct description of the 3D magnetic field stochasticity in turbulent fluids. This ability is ensured by fast magnetic reconnection in turbulent fluids and puts forward the concept of reconnection diffusion at the core of the physical picture of heat transfer in astrophysical plasmas. Appealing to reconnection diffusion we describe the ability of plasma to diffuse between different magnetized eddies explaining the advection of the heat by turbulence. Adopting the structure of magnetic field that follows from the modern understanding of MHD turbulence, we also discuss thermal conductivity that arises as electrons stream along stochastic magnetic field lines. We compare the effective heat transport that arise from the two processes and conclude that in many astrophysically-motivated cased eddy advection of heat dominates. Finally, we discuss the concepts of sub and superdiffusion and show that the subdiffusion requires rather restrictive settings. At the same time, accelerated diffusion or superdiffusion of heat is possible on the scales less than the injection scale of the turbulence.
Acceleration of Energetic Particles through Reconnection of Weakly Stochastic Magnetic Field
天体物理介质是湍流的，因此重联应该在存在预先存在的湍流的情况下进行处理。我们考虑Lazarian & Vishniac（1999）的快速磁重联模型，该模型预言重联速率受湍流运动的强度和注入尺度的控制。我们提供了新的证据，成功的测试模型，并认为该模型提出了一个通用的设置为天体物理重联事件。我们研究粒子加速，发生在体积的驱动湍流以及湍流体积中存在的大规模重联。我们证明，在后一种情况下，加速度是一阶费米型，从而支持Gouveia dal Pino和Lazarian（2005）提出的加速度模型。
Numerical Models for the Diffuse Ionized Gas in Galaxies. I. Synthetic spectra of thermally excited gas with turbulent magnetic reconnection as energy source
Disc formation in turbulent cloud cores: is magnetic flux loss necessary to stop the magnetic braking catastrophe or not?
Santos-Lima、de Gouveia Dal Pino和Lazarian（2012年）最近对湍流磁化云核中开普勒盘形成的数值分析表明，重联扩散是一个有效的过程，可以在旋转支撑盘的形成过程中去除多余的磁通量。这个过程是由湍流中磁场的快速重联引起的。在一项类似的数值研究中，Seifried等人（2012年）得出结论，重联扩散或任何其他非理想MHD效应都是不必要的，仅湍流剪切就可以提供一种自然的方式来建立旋转盘，而不需要磁通量损失。他们的结论是基于这样一个事实，即在半径远大于圆盘的球形区域上计算的平均质量通量比（μ）在他们的模型中几乎是恒定的。在这封信中，我们比较了两组模拟，并表明这种在大尺度上的平均可以掩盖在圆盘形成的内部区域μ的显着实际增加。我们表明，在吸积的湍流包络材料中，在盘形成的初始阶段发生了磁场的重联扩散。我们的分析是暗示，重连扩散是存在于这两套模拟，并提供了一个简单的解决方案的“磁制动灾难”，这是在文献中讨论的形成原恒星吸积盘。
