Hubble Space Telescope Observations of the CfA Seyfert 2 Galaxies: The Fueling of Active Galactic Nuclei
Hubble Space Telescope Observations of the CfA Seyfert 2 Galaxies: The Fueling of Active Galactic Nuclei
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DOI：
10.1086/301140
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发表时间：
1999-09
期刊：
影响因子：
--
通讯作者：
P. Martini;R. Pogge
中科院分区：
文献类型：
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作者：
P. Martini;R. Pogge
我们提出了一个调查可能的燃料机制在内部千秒差距的塞弗特星系。我们分析了可见光和近红外哈勃空间望远镜图像的24个塞弗特2星系的CfA红移调查样本。特别是，我们正在寻找负责运输气体从千秒差距尺度到核的动力学过程的形态特征。环核区域的气体和尘埃非常丰富，经常以几百秒差距尺度的核螺旋尘埃带的形式出现。虽然这些核螺旋在我们的24个塞弗特星系中的20个中被发现，但我们在整个样本中只发现了5个核棒，这强烈地加强了其他研究人员的结论，即核棒不是将这种物质运送到核中的主要手段。根据消光测量，对核螺旋中气体密度的估计表明，核螺旋尘埃带可能是核气体盘中的冲击，而不是强烈的自引力。由于冲击波可以耗散能量和角动量，这些螺旋尘埃带可能是宿主星系盘中的气体被送入中央引擎的通道。
We present an investigation of possible fueling mechanisms operating in the inner kiloparsec of Seyfert galaxies. We analyze visible and near-infrared Hubble Space Telescope images of 24 Seyfert 2 galaxies from the CfA Redshift Survey sample. In particular, we are searching for the morphological signatures of dynamical processes responsible for transporting gas from kiloparsec scales into the nucleus. The circumnuclear regions are very rich in gas and dust, often taking the form of nuclear spiral dust lanes on scales of a few hundred parsecs. While these nuclear spirals are found in 20 of our 24 Seyfert galaxies, we find only five nuclear bars among the entire sample, strongly reinforcing the conclusions of other investigators that nuclear bars are not the primary means of transporting this material into the nucleus. An estimate of the gas density in the nuclear spirals, based on extinction measurements, suggests that the nuclear spiral dust lanes are probably shocks in nuclear gas disks that are not strongly self-gravitating. Since shocks can dissipate energy and angular momentum, these spiral dust lanes may be the channels by which gas from the host galaxy disks is being fed into the central engines.