Dark Filaments in the Galaxy NGC 253: A Boiling Galactic Disk
Dark Filaments in the Galaxy NGC 253: A Boiling Galactic Disk
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银河系 NGC 253 中的暗丝：沸腾的银盘
DOI：
10.1086/117222
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发表时间：
1994
期刊：
影响因子：
--
通讯作者：
D. Malin
中科院分区：
文献类型：
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作者：
Y. Sofue;K. Wakamatsu;D. Malin
我们使用一张不清晰的$B$波段光学照片研究了富尘星系NGC 253中暗带和暗丝的形态。尘埃特征被分类为“弧”，其高度和尺度半径约为100至300 pc，连接两个或更多的乌云，以及“环”和“气泡”，这是弧的发展形式，扩展到盘晕界面。它们的直径为几百pc到$\sim 1$ kpc。在这些气泡中，我们注意到在核的上方有一个奇特的圆形气泡，这可能是一个大直径（300秒差距）的超新星残骸在核的晕中爆炸。我们还发现了“垂直尘埃流”，它包括一束窄丝，厚度为几十pc，几乎垂直于银道面，向晕相干延伸1至2千秒差距。最后，我们注意到在中心区域发现了“短的垂直尘埃丝”（或针状物）。我们解释这些功能是由于三维结构的气体从磁盘延伸到晕。我们提出了一个“沸腾盘”的模型，其中的附属功能所产生的恒星形成活动的磁盘，以及磁通量的影响。我们讨论的ISM在星系盘的化学演化模型的含义。
We study the morphology of dark lanes and filaments in the dust-rich galaxy NGC 253 using an unsharp-masked $B$-band optical photograph. Dust features are classified as `arcs', which have heights and scale radius of about 100 to 300 pc, connecting two or more dark clouds, and `loops' and `bubbles', which are developed forms of arcs, expanding into the disk-halo interface. These have diameters of a few hundred pc to $\sim 1$ kpc. Among the bubbles, we notice a peculiar round-shaped bubble above the nucleus, which could be a large-diameter ($\sim 300$ pc) supernova remnant exploded in the halo over the nucleus. We also find `vertical dust streamers', which comprise bunches of narrow filaments with a thickness of a few tens of pc and are almost perpendicular to the galactic plane, extending coherently for 1 to 2 kpc toward the halo. Finally, we note `short vertical dust filaments' (or spicules) are found in the central region. We interpret these features as due to three-dimensional structures of gas extending from the disk into the halo. We propose a `boiling disk' model where the filamentary features are produced by star-forming activity in the disk as well as the influence of magnetic fluxes. We discuss the implication of the model for the chemical evolution of the ISM in a galaxy disk.