论文标题
密集核碰撞的MHD模拟
MHD simulations of dense core collision
论文作者
论文摘要
我们研究了磁场对密集分子核之间碰撞过程的影响。我们使用ENZO自适应网格改进代码对两个自我磨损核之间的碰撞进行了三维磁流失动力学模拟。将核心建模为稳定的等温邦诺·埃伯特（BE）球，浸入均匀的磁场中。碰撞的特征是偏移参数$ b $，初始核心$ \ MATHCAL {M} $的马赫数，磁场强度$ b_ {0} $，以及初始磁场和碰撞轴之间的角度$θ$。对于正面的（$ b = 0 $）碰撞，在压缩层中形成了一个原始的。磁场强度越高，吸积率越低。对于$ b = 0 $和$θ= 90^{\ circ} $的型号，吸积率更依赖于初始磁场强度，而$ b = 0 $和$θ= 0^{\ circ} $模型。对于中心（$ b = 1 $）的碰撞，更高的角度动量增加了；因此，气体运动很复杂。在具有$ b = 1 $和$ \ MATHCAL {M} = 1 $的型号中，Protostars和Gas Motion的数量高度依赖于$ B_ {0} $和$θ$。对于$ b = 1 $和$ \ MATHCAL {M} = 3 $的型号，没有形成重大的冲击压缩层，并且未触发恒星形成。
We investigated the effect of magnetic fields on the collision process between dense molecular cores. We performed three-dimensional magnetohydrodynamic simulations of collisions between two self-gravitating cores using the Enzo adaptive mesh refinement code. The core was modeled as a stable isothermal Bonnor-Ebert (BE) sphere immersed in uniform magnetic fields. Collisions were characterized by the offset parameter $b$, Mach number of the initial core $\mathcal{M}$, magnetic field strength $B_{0}$, and angle $θ$ between the initial magnetic field and collision axis. For head-on ($b = 0$) collisions, one protostar was formed in the compressed layer. The higher the magnetic field strength, the lower the accretion rate. For models with $b = 0$ and $θ= 90^{\circ}$, the accretion rate was more dependent on the initial magnetic field strength compared with $b = 0$ and $θ= 0^{\circ}$ models. For off-center ($b = 1$) collisions, the higher specific angular momentum increased; therefore, the gas motion was complicated. In models with $b = 1$ and $\mathcal{M} = 1$, the number of protostars and gas motion highly depended on $B_{0}$ and $θ$. For models with $b = 1$ and $\mathcal{M} = 3$, no significant shock-compressed layer was formed and star formation was not triggered.
