Collapse and fragmentation of rotating magnetized clouds — I. Magnetic flux-spin relation
Collapse and fragmentation of rotating magnetized clouds — I. Magnetic flux-spin relation
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DOI：
10.1111/j.1365-2966.2005.09297.x
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发表时间：
2005-06
影响因子：
4.8
通讯作者：
M. Machida;Tomoaki Matsumoto;K. Tomisaka;T. Hanawa
中科院分区：
文献类型：
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作者：
M. Machida;Tomoaki Matsumoto;K. Tomisaka;T. Hanawa
在三维数值模拟的基础上，讨论了分子云核的磁通密度和角速度的演化，在该过程中，旋转的磁化云碎裂并坍缩形成一个非常致密的光学厚度大于5 × 1010 cm 3的核.随着密度朝着光学厚芯的形成增加，磁通量密度和角速度收敛到两个量之间的单一关系。如果核心是磁主导的，它的磁通量密度接近1.5（n/5 × 1010 cm 3）1/2 mG，而如果核心是旋转主导的，角速度接近2.57 × 103（n/5 × 1010 cm 3）1/2 yr-1，其中n是气体的密度。我们还发现，角速度与磁通量密度之比几乎保持恒定，直到密度超过5 × 1010 cm 3。在随后的论文中显示了非常致密的核心的碎裂和碎片流出的出现。
We discuss evolution of the magnetic flux density and angular velocity in a molecular cloud core, on the basis of three-dimensional numerical simulations, in which a rotating magnetized cloud fragments and collapses to form a very dense optically thick core of > 5 × 10 10 cm 3 . As the density increases towards the formation of the optically thick core, the magnetic flux density and angular velocity converge towa rds a single relationship between the two quantities. If the core is magnetically dominated it s magnetic flux density approaches 1.5(n/5 × 10 10 cm 3 ) 1/2 mG, while if the core is rotationally dominated the angular velocity approaches 2.57 × 10 3 (n/5 × 10 10 cm 3 ) 1/2 yr 1 , where n is the density of the gas. We also find that the ratio of the angular velocity to the magne tic flux density remains nearly constant until the density exceeds 5 × 10 10 cm 3 . Fragmentation of the very dense core and emergence of outflows from fragments are shown in the subsequ ent paper.