论文标题
分子粉碎
Molecular Shattering
论文作者
论文摘要
最近的观察结果表明，星系可能会普遍存在将分子成分托管到其多相呈近期培养基（CGM）。然而，分子CGM的结构和运动学在理论上和很大程度上都在观察上进行了研究。最近的工作表明，在类似于原子云的热风中，有效冷却的分子气云在加速中存活。然而，当受到外部冲击或进行冷却时，分子云的压力驱动碎片仍未被研究。我们对云的辐射性，无粘性的流体动力学模拟，对压力平衡扰动的云，以探索流体动力学碎片的过程，从而探索分子温度的过程。我们发现大于临界大小的分子云可能会碎成微小的液滴的雾气，而临界大小与原子情况显着偏离。我们发现，只有当声音交叉时间超过冷却时间的局部最大值〜8000 k时，冷云才会崩溃。此外，我们发现证据表明，由于旋转碎片的结果，我们发现将冷云碎成“粉云”的小滴的“雾气” - 这是一个旋转碎片的结果 - 一个过程 - 我们配音了“分裂”。我们的结果对在观测和宇宙学模拟中解决CGM的分子相具有影响。
Recent observations suggest galaxies may ubiquitously host a molecular component to their multiphase circumgalactic medium (CGM). However, the structure and kinematics of the molecular CGM remains understudied theoretically and largely unconstrained observationally. Recent work suggests molecular gas clouds with efficient cooling survive acceleration in hot winds similar to atomic clouds. Yet the pressure-driven fragmentation of molecular clouds when subjected to external shocks or undergoing cooling remains unstudied. We perform radiative, inviscid hydrodynamics simulations of clouds perturbed out of pressure equilibrium to explore the process of hydrodynamic fragmentation to molecular temperatures. We find molecular clouds larger than a critical size can shatter into a mist of tiny droplets, with the critical size deviating significantly from the atomic case. We find that cold clouds shatter only if the sound crossing time exceeds the local maximum of the cooling time ~8000 K. Moreover, we find evidence for a universal mechanism to 'shatter' cold clouds into a 'mist' of tiny droplets as a result of rotational fragmentation -- a process we dub 'splintering.' Our results have implications for resolving the molecular phase of the CGM in observations and cosmological simulations.
