论文标题
Ultrastrong田间制度中磁铁的磁流失动力学稳定性II：地壳
Magnetohydrodynamic stability of magnetars in the ultrastrong field regime II: The crust
论文作者
论文摘要
我们研究了Hall MHD的稳定性，具有强磁场，其中Landau对电子的量化很重要。我们发现，强场大厅模式可能会因差异磁化率对磁场强度的依赖性而不稳定。使用线性扰动理论研究了这种不稳定性，并发现具有典型的增长时间$ \ lyssim 10^3 $ yrs，其增长时间随扰动波长的函数而减少。不稳定性是自限制的，在一段时间的局部田间增长量增加了初始值的百分之几之后。还显示有限温度可以限制不稳定性，并完全消除了它的足够高温。 Alfvén波可以在较短的时间尺度上显示出相似的不稳定行为。我们发现，由于通过不稳定性而开发的大田而引起的欧姆加热，磁性域的形成不足以说明观察到的磁性表面温度。然而，通过陆豪定量电子的振荡差分磁化率增强了欧姆的加热，这对于中子星形壳的磁热模拟可能很重要。
We study the stability of Hall MHD with strong magnetic fields in which Landau quantization of electrons is important. We find that the strong-field Hall modes can be destabilized by the dependence of the differential magnetic susceptibility on magnetic field strength. This instability is studied using linear perturbation theory, and is found to have typical growth time of order $\lesssim 10^3$ yrs, with the growth time decreasing as a function of wavelength of the perturbation. The instability is self-limiting, turning off following a period of local field growth by a few percent of the initial value. Finite temperature is also shown to limit the instability, with sufficiently high temperatures eliminating it altogether. Alfvén waves can show similar unstable behaviour on shorter timescales. We find that Ohmic heating due to the large fields developed via the instability and magnetic domain formation is not large enough to account for observed magnetar surface temperatures. However, Ohmic heating is enhanced by the oscillatory differential magnetic susceptibility of Landau-quantized electrons, which could be important to magneto-thermal simulations of neutron star crusts.
