Gravitational torques and star formation
Gravitational torques and star formation
复制标题
引力力矩和恒星形成
DOI：
10.1093/mnras/206.1.197
复制
发表时间：
1984
影响因子：
4.8
通讯作者：
R. Larson
中科院分区：
文献类型：
--
作者：
R. Larson
坍缩云结构中出现的任何不规则性都会产生非径向引力，如果这种不规则性被差动旋转剪切成大振幅的拖尾螺旋特征，则相关的引力矩将在轨道时间尺度上向外传递角动量。即使在坍缩过程中没有发生角动量的重新分布，并且形成了一个扁平的盘状结构，这样的盘充其量也是一个脆弱的结构，并且在现实的初始条件下，它对于尾螺旋密度增强的发展是非常不稳定的。因此，在一个实际的坍缩云中，似乎不可避免地迟早会发生由引力矩引起的角动量的迅速向外转移。坍缩的唯一稳定结果将是这样一个系统，其中大部分质量都在中心星星或双星系统中，只有不到一半的质量留在星星周围的圆盘中;只有不到四分之一的质量留在我们太阳系大小的圆盘中。
Any irregularities that occur in the structure of a collapsing cloud will produce non-radial gravitational forces and, if such irregularities are sheared by differential rotation into trailing spiral features of large amplitude, the associated gravitational torques will transfer angular momentum outward on an orbital time-scale. Even if no redistribution of angular momentum occurs during the collapse and a flattened disc-like configuration is formed, such a disc will be a fragile structure at best, and with realistic initial conditions it will be highly unstable to the development of trailing spiral density enhancements. Thus it seems inescapable that in a realistic collapsing cloud there will sooner or later occur rapid outward transfer of angular momentum by gravitational torques. The only stable outcome of the collapse will then be a system in which most of the mass is in a central star or binary system, and less than half remains in a disc around the star; less than one-quarter can remain in a disc with the size of our Solar System.