论文标题
原星磁盘中的星形磁盘对准：湍流分子云芯塌陷的SPH模拟
Star-disk alignment in the protoplanetary disks: SPH simulation of the collapse of turbulent molecular cloud cores
论文作者
论文摘要
我们执行一系列三维平滑颗粒流体动力学（SPH）模拟，以研究原始旋转和原始磁盘旋转轴（星形角度$ψ_{\ rm sd} $）在湍流分子云核中的角度演变。 $ψ_ {\ rm sd} $在Protostar Epoch上表现出广泛的分布至$ \ sim 130^{\ circ} $，$ψ_ {\ rm sd} $减少（$ \ lyssim 20^{\ circ} $），in Timescale of of $ \ sim \ sim \ sim simcale of of $ \ sim \ sim simcale of simcale星形对齐的时间尺度，$ t _ {\ rm对齐} $，基本上对应于中央原恒星的质量加倍时间，在该时间上，由于磁盘的质量积聚，原恒星忘记了其最初的旋转方向。 $ψ_ {\ rm sd} $的值都在$ t = 10^2 $ yr和$ t = 10^5 $ yr之后，原恒星形成后独立于热和动荡的能量与初始云核的引力与引力的比率：$α= e _ = e _ = e _ {\ rm thermal}/| e e _ = $γ_ {\ rm turb} = e _ {\ rm turburece}/| e _ {\ rm gravity} | $。我们还发现，扭曲的磁盘可能是由脉动信封的湍流积聚流形成的。
We perform a series of three-dimensional smoothed particle hydrodynamics (SPH) simulations to study the evolution of the angle between the protostellar spin and the protoplanetary disk rotation axes (the star-disk angle $ψ_{\rm sd}$) in turbulent molecular cloud cores. While $ψ_{\rm sd}$ at the protostar formation epoch exhibits broad distribution up to $\sim 130^{\circ}$, $ψ_{\rm sd}$ decreases ($\lesssim 20^{\circ}$) in a timescale of $\sim 10^{4}$ yr. This timescale of the star-disk alignment, $t_{\rm alignment}$, corresponds basically to the mass doubling time of the central protostar, in which the protostar forgets its initial spin direction due to the mass accretion from the disk. Values of $ψ_{\rm sd}$ both at $t=10^2$ yr and $t=10^5$ yr after the protostar formation are independent of the ratios of thermal and turbulent energies to gravitational energy of the initial cloud cores: $α=E_{\rm thermal}/|E_{\rm gravity}|$ and $γ_{\rm turb}=E_{\rm turbulence}/|E_{\rm gravity}|$. We also find that a warped disk is possibly formed by the turbulent accretion flow from the circumstellar envelope.
