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arXiv 0901.1704astro-ph.GA
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NGC 1068窄线区的运动学和激发结构

Kinematic and Excitation Structure of the NGC 1068 Narrow-Line Region

Shinobu Ozaki

摘要:

我们研究了NGC 1068窄线区(NLR)的运动学和激发结构。我们在高速分辨率(R ~ 7500 - 11000)下获得了几条发射线的轮廓,[OIII] $λ$ 5007,H $β$,[OI] $λ$ 6300和[FeVII] $λ$ 6087,并证实它们显示出不同的轮廓。这些配置文件是有用的理解NLR结构,因为它们涵盖了广泛的电离电位范围。通过与光电离模型的比较,我们发现:(1)中心的蓝移成分非常密集;(2)东北部的蓝移成分密度略低于中心的蓝移成分;(3)蓝移成分的电离参数随着相对于系统速度的速度的增加而增加。基于这些结果,我们研究了NGC 1068中的NLR结构。我们发现,所观察到的速度依赖性的电离参数和逐渐增加的速度场可以通过改变电离连续衰减再现,假设一个中空的双锥几何形状和不同的外流云的柱密度。

英文摘要:

We investigated the kinematic and excitation structure of the NGC 1068 narrow-line region (NLR). We obtained profiles of several emission lines, [OIII]$λ$5007, H$β$, [OI]$λ$6300 and [FeVII]$λ$6087 at high-velocity resolution (R ~ 7500 - 11000), and confirmed that they showed different profiles. These profiles are useful for understanding the NLR structure, as they cover a wide ionization potential range. By comparing the results with a photoionization model, we found that 1) blueshifted components at the center are very dense, 2) those in the northeast region have slightly lower densities than those in the center, and 3) ionization parameters of the blueshifted components increase with increasing velocity with respect to the systemic velocity. We investigated the NLR structure in NGC 1068 based on these results. We show that both the observed velocity dependence of the ionization parameter and the gradually increasing velocity field can be reproduced by varying the ionizing continuum attenuation, assuming a hollowed biconical geometry and varying the column densities of outflowing clouds.

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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