标题： 揭示星团形成云核的动力学：角动量和磁场性质的三维磁流体力学模拟研究 显示英文标题

标题： Unveiling the Dynamics of Dense Cores in Cluster-Forming Clumps: A 3D MHD Simulation Study of Angular Momentum and Magnetic Field Properties

摘要： 我们进行了等温MHD模拟，并考虑了自引力，以研究星团形成云块中的致密核的性质。探索了两种不同的设置：单个旋转云块和碰撞云块。我们的重点是确定形成的致密核继承其母云块旋转和磁场的程度。我们的统计分析表明，致密核角动量 $\bf{L}_{\rm core}$ 和云块旋转轴之间的对齐受湍流强度和模拟设置的影响。在单个旋转云块中，如果初始湍流较弱，发现 $\bf{L}_{\rm core}$ 趋向于与云块的旋转轴对齐。然而，在碰撞云块中，无论初始湍流强度如何，这种对齐不会发生。碰撞云块中的这种错位是由于碰撞诱导的湍流以及气体向致密核的各向同性流入引起的。我们对碰撞云块的分析还显示，磁场在全球范围内沿着冲击压缩层弯曲，而致密核的平均磁场 $\bf{B}_{\rm core}$ 与其对齐。在单个旋转云块和碰撞云块中，我们都发现 $\bf{B}_{\rm core}$ 和 $\bf{L}_{\rm core}$ 之间的角度通常是随机的，与云块属性无关。我们还分析了形成的核的动力学状态，并发现在碰撞云块中无束缚核的比例更高。此外，无论模型参数如何，无论是单个还是碰撞情况，旋转能量的贡献仅约占引力能量的5%。 显示英文摘要

摘要： We conducted isothermal MHD simulations with self-gravity to investigate the properties of dense cores in cluster-forming clumps. Two different setups were explored: a single rotating clump and colliding clumps. We focused on determining the extent to which the formed dense cores inherit the rotation and magnetic field of the parental clump. Our statistical analysis revealed that the alignment between the angular momentum of dense cores, $\bf{L}_{\rm core}$, and the rotational axis of the clump is influenced by the strength of turbulence and the simulation setup. In single rotating clumps, we found that $\bf{L}_{\rm core}$ tends to align with the clump's rotational axis if the initial turbulence is weak. However, in colliding clumps, this alignment does not occur, regardless of the initial turbulence strength. This misalignment in colliding clumps is due to the induced turbulence from the collision and the isotropic gas inflow into dense cores. Our analysis of colliding clumps also revealed that the magnetic field globally bends along the shock-compressed layer, and the mean magnetic field of dense cores, $\bf{B}_{\rm core}$, aligns with it. Both in single rotating clumps and colliding clumps, we found that the angle between $\bf{B}_{\rm core}$ and $\bf{L}_{\rm core}$ is generally random, regardless of the clump properties. We also analyzed the dynamical states of the formed cores and found a higher proportion of unbound cores in colliding clumps. In addition, the contribution of rotational energy was only approximately 5% of the gravitational energy, regardless of the model parameters for both single and colliding cases.