POSSIBLE EXPLANATIONS FOR SOME UNUSUALLY LARGE VELOCITY DISPERSION MOLECULAR CLOUDS NEAR THE GALACTIC CENTRE
POSSIBLE EXPLANATIONS FOR SOME UNUSUALLY LARGE VELOCITY DISPERSION MOLECULAR CLOUDS NEAR THE GALACTIC CENTRE
复制标题
对银心附近一些异常大速度色散分子云的可能解释
DOI：
10.1093/mnras/292.4.871
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发表时间：
1997
影响因子：
4.8
通讯作者：
H. Riffert
中科院分区：
文献类型：
--
作者：
Pawan Kumar;H. Riffert
银河系中心区域的分子云通常有一个速度色散，与银河系其他地方类似质量云的速度色散相比，它几乎可以大2倍。然而，至少有两个巨大的分子云，也许多达六个，位于银河系中心的一个千秒差距内，具有内部随机速度，在12 CO和H I发射线中观察到，从大约0到几乎200 km S-I。它比正常的巨型分子云大约大10倍。两个最突出的云有一个分子质量，估计从12 CO排放，“106 Mo”和它们的原子氢质量约为2 × 105 Mo。我们考虑各种可能的物理机制，这些云的大速度色散。
Molecular clouds in the Galactic Centre region typically have a velocity dispersion that can be larger by almost a factor of 2 compared with the velocity dispersion of similar mass clouds elsewhere in the Galaxy. However, there are at least two giant molecular clouds, and perhaps as many as half a dozen, located within a kpc of the Galactic Centre that have internal random velocities, observed in 12CO and H I emission lines, that extend from about 0 to almost 200 km S-I. This is larger by a factor of about 10 than normal giant molecular clouds. Two of the most prominent clouds have a molecular mass, estimated from the 12CO emission, of '" 106 Mo' and their atomic hydrogen mass is about 2 x 105 Mo' We consider various possible physical mechanisms for the large velocity dispersion of these clouds.