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arXiv 1105.1735astro-ph.GAastro-ph.CO
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巨星系NGC1275周围暗条的能量来源

The energy source of the filaments around the giant galaxy NGC1275

A. C. Fabian, J. S. Sanders, R. J. R. Williams, A. Lazarian, G. J. Ferland, R. M. Johnstone

摘要:

英仙座星系团附近最明亮的星系NGC1275被一个丝状网络包围着。它们最初是通过它们的H α发射被观测到的,但现在已知它们有一个大分子成分,总质量接近10^11兆太阳能。这些细丝嵌入在炽热的团内气体中,延伸超过80千秒差距。它们有一个不寻常的低激发光谱,这是很好地模拟碰撞加热和电离的次级电子。在这里,我们注意到,从外部细丝的表面辐射通量是接近的能量通量影响他们从热气体中的粒子。我们提出,冷灯丝内的次级电子,激发所观察到的亚毫米通过UV发射,是由于周围的热气体有效地穿透冷气体通过重连扩散。从灯丝中看到的一些软X射线发射是由于电荷交换,尽管这不足以解释所有观测到的X射线通量。纤维是复杂的多相气体。冷热气体的相互渗透导致了细丝的质量增长,速度高达100 Msunpyr。在冷的核心星系团中缺乏软X射线冷却发射是由于热气体与中心星系周围和内部的冷气体混合时的非辐射冷却。

英文摘要:

The brightest galaxy in the nearby Perseus cluster, NGC1275, is surrounded by a network of filaments. These were first observed through their Halpha emission but are now known to have a large molecular component with a total mass approaching 10^11Msun of gas. The filaments are embedded in hot intracluster gas and stretch over 80 kpc. They have an unusual low excitation spectrum which is well modelled by collisional heating and ionization by secondary electrons. Here we note that the surface radiative flux from the outer filaments is close to the energy flux impacting on them from particles in the hot gas. We propose that the secondary electrons within the cold filaments, which excite the observed submillimetre through UV emission, are due to the hot surrounding gas efficiently penetrating the cold gas through reconnection diffusion. Some of the soft X-ray emission seen from the filaments is then due to charge exchange, although this is insufficient to account for all the observed X-ray flux. The filaments are complex with multiphase gas. Interpenetration of hot and cold gas leads to the filaments growing in mass, at a rate of up to 100Msunpyr. The lack of soft X-ray cooling emission in cool core clusters is then due to the non-radiative cooling of hot gas on mixing with cold gas around and within the central galaxy.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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