论文标题
圆盘厚度和粘度的调查：二进制进化，可变性和椎间盘形态
A Survey of Disc Thickness and Viscosity in Circumbinary Accretion: Binary Evolution, Variability, and Disc Morphology
论文作者
论文摘要
与天体物理圆形积聚盘的演变有关的大部分参数空间尚未探索。我们进行了一套电路盘模拟的套件，使用常数$ν$和常数$ $α$处方，调查了圆盘厚度和运动粘度。我们主要专注于$ 0.1 $至$ 0.033 $的光盘纵横比，以及$ν= 0.0005 $和$ν= 0.008 $（以二进制半轴轴和轨道频率的单位）之间的粘度，并专门用于循环相等质量的binaries。这两个因素都强烈影响了二进制半束轴的演变：在$ν= 0.0005时，$ simple $以宽高比$ \ lyssim0.059 $出现，而$ν= 0.004 $ simple仅出现在长宽比$ \ sillsimsim0.04 $上。 Inspirals的出现很大程度上是由于滞后二进制的材料流在二进制上的越来越强的负扭矩，而在环形盘中激发的谐振扭矩的贡献微不足道。我们发现，当模拟与二进制相互作用驱动的最终的准稳态状态过远时，积聚率的降低会发生，而不是与圆盘纵横比的相互作用。我们发现，随着粘度的降低，腔尺寸不仅会增加，而且较薄的电圆盘变得更加偏心。我们的结果表明，超级黑洞二进制文件应比以前的估计更快地驱动，从$ \ sim $ parsec分离到引力波驱动其灵感的距离，从而有可能减少脉冲星时正时阵列可观察到的二进制数量。
Much of the parameter space relevant to the evolution of astrophysical circumbinary accretion discs remains unexplored. We have carried out a suite of circumbinary disc simulations surveying both disc thickness and kinematic viscosity, using both constant-$ν$ and constant-$α$ prescriptions. We focus primarily on disc aspect ratios between $0.1$ and $0.033$, and on viscosities between $ν=0.0005$ and $ν=0.008$ (in units of binary semi-major axis and orbital frequency), and specialise to circular equal-mass binaries. Both factors strongly influence the evolution of the binary semi-major axis: at $ν=0.0005,$ inspirals occur at aspect ratios $\lesssim0.059$, while at $ν=0.004$ inspirals occur only at aspect ratios $\lesssim0.04$. Inspirals occur largely because of the increasingly strong negative torque on the binary by streams of material which lag the binary, with negligible contributions from resonant torques excited in the circumbinary disc. We find that reductions in accretion rate occur when simulations are initialised too far from the eventual quasi-steady state driven by interaction with the binary, rather than being intrinsically linked to the disc aspect ratio. We find not only that the cavity size increases as viscosity is decreased, but that thinner circumbinary discs become more eccentric. Our results suggest that supermassive black hole binaries should be driven, more rapidly than previous estimates, from $\sim$parsec separations to distances where gravitational waves drive their inspiral, potentially reducing the number of binaries observable by pulsar timing arrays.
