论文标题
通量喷发事件驱动磁性逮捕的积聚流动的角动量转运
Flux eruption events drive angular momentum transport in magnetically arrested accretion flows
论文作者
论文摘要
我们进化了两个高分辨率的相对论磁性水力动力学（GRMHD）模拟，以在非旋转黑洞（BHS）周围为主导的积聚流动（BHS），每个都在持续时间内$ \ sim 3 \ sim 3 \ times 10^5 \，gm _ {\ rm bh}/c^3 $。一种模型捕获了弱磁化（SANE）磁盘的演变，另一个模型是磁性被捕的磁盘（MAD）的演变。疯狂模型中的磁通量爆发从磁盘上驱出气体，并发出强风，有时会达到$ 10 \％$ $ $ $ $ $。尽管在这些风中具有很大的功率，但平均质量流出率仍然很小，直到半径为$ \ sim100 \，gm _ {\ rm bh}/c^2 $，仅达到$ \ sim 60-80 \％\％\％\％\％\％。在两种吸收模式下，平均向外动量传输主要是径向的，但是具有明显的区别：磁通量触发驱动驱动的磁盘风在疯狂模型中导致角动量的垂直垂直流，而对于Sane模型，磁极模型（MRI）在磁极动力（MRI）移动了角动力，大多数通过磁盘移动了角度的均值。此外，我们发现疯狂的状态是高度暂时的，非轴对称性，在喷发后，增生模式通常会变为平理状态，然后随着时间的时间重新振动磁通量饱和。雷诺（Reynolds）的压力在此类过渡期间改变了方向，疯狂（理智）状态表现出内向（向外）的压力，可能指出MAD中的间歇性MRI驱动积聚。使用下一代望远镜钉住通量爆发的性质对于理解质量，磁通量和角动量的流动至关重要。
We evolve two high-resolution general relativistic magnetohydrodynamic (GRMHD) simulations of advection-dominated accretion flows around non-spinning black holes (BHs), each over a duration $\sim 3\times 10^5\,GM_{\rm BH}/c^3$. One model captures the evolution of a weakly magnetized (SANE) disk and the other a magnetically arrested disk (MAD). Magnetic flux eruptions in the MAD model push out gas from the disk and launch strong winds with outflow efficiencies at times reaching $10\%$ of the incoming accretion power. Despite the substantial power in these winds, average mass outflow rates remain small out to a radius $\sim100\,GM_{\rm BH}/c^2$, only reaching $\sim 60-80\%$ of the horizon accretion rate. The average outward angular momentum transport is primarily radial in both modes of accretion, but with a clear distinction: magnetic flux eruption-driven disk winds cause a strong vertical flow of angular momentum in the MAD model, while for the SANE model, the magnetorotational instability (MRI) moves angular momentum mostly equatorially through the disk. Further, we find that the MAD state is highly transitory and non-axisymmetric, with the accretion mode often changing to a SANE-like state following an eruption before reattaining magnetic flux saturation with time. The Reynolds stress changes direction during such transitions, with the MAD (SANE) state showing an inward (outward) stress, possibly pointing to intermittent MRI-driven accretion in MADs. Pinning down the nature of flux eruptions using next-generation telescopes will be crucial in understanding the flow of mass, magnetic flux and angular momentum in sub-Eddington accreting BHs like M87$^*$ and Sagittarius A$^*$.
