论文标题
关于黑洞的积聚磁盘中的超级alfvénic旋转不稳定性
The Super-Alfvénic Rotational Instability in accretion disks about black holes
论文作者
论文摘要
关于黑洞，中子恒星或原始行星的积聚磁盘不稳定理论是通过光谱网的最新方法来重新审视的。圆柱体吸积盘微分方程被证明由前向和向后的多普勒转移连续的alfvén光谱$ω_ {\ rm a}^\ pm \ equivmΩ\ equivmΩ\ pmω_ {\ rm a} $ {\ rm a} $，其中$ω_} $ rm a}将非轴对称性（$ M \ ne 0 $）和多普勒框架（$ |mΩ| \ gg |ω_ {\ rm a} | $）进行考虑至关重要。 continua $ω_ {\ rm a}^+$和$ω_ {\ rm a}^ - 然后重叠，弹出了众多的超级alfvénic旋转稳定性（saris）。对小不均匀性的深入分析表明，两个alfvén奇异性将模式的程度降低到比积分磁盘宽度小得多的大小。大型不均匀性的概括导致完全前所未有的结果，对于模式编号$ | k | \ gg | m | $，在真实轴的广阔社区中的任何复杂的$ω$都是近似的“特征值”。与真正的特征模式的区别在于，激发模式的互补能量量很小，$ | w _ {\ rm com} | \ le c $，带有$ c $计算的机器精度。这产生了准二葡萄酒模式的二维连续性：准continuum纱丽。我们猜想磁化磁盘中3D湍流的发作不是由离散的轴对称磁性旋转不稳定性激发的，而是通过激发这些二维连续性的模式的激发，这些二维连续性是Quasi-Discrete discrete non-axiSypcrete non-axipertrice non-axipsymmetric no-axipsymmetric Super-Alfvénic旋转式旋转率。
The theory of instability of accretion disks about black holes, neutron stars or proto-planets, is revisited by means of the recent method of the Spectral Web. The cylindrical accretion disk differential equation is shown to be governed by the forward and backward Doppler-shifted continuous Alfvén spectra $Ω_{\rm A}^\pm \equiv m Ω\pm ω_{\rm A}$, where $ω_{\rm A}$ is the static Alfvén frequency. It is crucial to take non-axisymmetry ($m \ne 0$) and super-Alfvénic rotation of the Doppler frames ($|mΩ| \gg |ω_{\rm A}|$) into account. The continua $Ω_{\rm A}^+$ and $Ω_{\rm A}^-$ then overlap, ejecting a plethora of Super-Alfvénic Rotational Instabilities (SARIs). In-depth analysis for small inhomogeneity shows that the two Alfvén singularities reduce the extent of the modes to sizes much smaller than the width of the accretion disk. Generalization for large inhomogeneity leads to the completely unprecedented result that, for mode numbers $|k| \gg |m|$, any complex $ω$ in a wide neighborhood of the real axis is an approximate `eigenvalue'. The difference with genuine eigenmodes is that the amount of complementary energy to excite the modes is tiny, $|W_{\rm com}| \le c$, with $c$ the machine accuracy of the computation. This yields a multitude of two-dimensional continua of quasi-discrete modes: quasi-continuum SARIs. We conjecture that the onset of 3D turbulence in magnetized accretion disks is governed, not by the excitation of discrete axisymmetric Magneto-Rotational Instabilities, but by the excitation of modes from these two-dimensional continua of quasi-discrete non-axisymmetric Super-Alfvénic Rotational Instabilities.
