The Three-dimensional Structure of a Massive Gas Disk in the Galactic Central Region
The Three-dimensional Structure of a Massive Gas Disk in the Galactic Central Region
复制标题
银河系中央区域巨大气盘的三维结构
DOI：
10.1086/323668
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发表时间：
2001
期刊：
影响因子：
--
通讯作者：
K. Wada
中科院分区：
文献类型：
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作者：
K. Wada
利用高分辨率的三维流体力学模拟，考虑了气体的自引力、10K到108K的辐射冷却和超新星的能量反馈，研究了星系中心100PC区星际介质(ISM)的结构。与Wada和Norman以前的二维结果类似，我们发现引力和热不稳定的ISM以自稳定的方式演化成准稳定的薄盘，其特征是由冷(T<；100K)致密团块和细丝组成的网络，以及热(T&gT；106K)扩散介质。超新星爆炸将扩散气体从盘面吹走，结果形成了一个准稳定的扩散晕，它不均匀，但具有羽状结构。准稳态下的密度概率分布函数可用对数正态函数在约7个数量级上进行很好的拟合。
Using high-resolution, three-dimensional hydrodynamical simulations, we investigate the structure of the interstellar medium (ISM) in the central 100 pc region in galaxies, taking into account the self-gravity of the gas, radiative cooling from 10 to 108 K, and energy feedback from supernovae. Similar to the previous two-dimensional results produced by Wada and Norman, we find that a gravitationally and thermally unstable ISM evolves, in a self-stabilizing manner, into a quasi-stable thin disk, which is characterized by a network of cold (T < 100 K) dense clumps and filaments, and a hot (T > 106 K) diffuse medium. Supernova explosions blow the diffuse gases from the disk, and as a result, a quasi-steady diffuse halo, which is not uniform but has a plumelike structure, is formed. The density probability distribution function in a quasi-steady state is well fitted by a lognormal function over about 7 orders of magnitude.