Spectral Models for Low-luminosity Active Galactic Nuclei in LINERs: The Role of Advection-dominated Accretion and Jets
Spectral Models for Low-luminosity Active Galactic Nuclei in LINERs: The Role of Advection-dominated Accretion and Jets
复制标题
DOI：
10.1093/mnras/stt2388
复制
发表时间：
2013-12
影响因子：
4.8
通讯作者：
R. Nemmen;T. Storchi-Bergmann;M. Eracleous
中科院分区：
文献类型：
--
作者：
R. Nemmen;T. Storchi-Bergmann;M. Eracleous
通过模拟12个低光度活动星系核（LLAGNs）低电离核发射线区（LINERs）的光谱能量分布（SED），对低光度活动星系核（LLAGNs）吸积流和喷流的物理性质进行了探索性研究。我们从黑洞附近的高分辨率无线电，X射线和光学/紫外线观测中构建了这些SED。我们采用一个由对流主导的吸积流（ADAF）和标准薄盘组成的吸积喷流耦合模型。我们提出了最好的t模型，其中无论是ADAF或喷气占主导地位的X射线发射。在我们的样本中显示opticalUV过剩相对于ADAF和喷气模型的六个来源，这种过剩可以解释为从截断盘发射过渡半径30 - 225 RS在其中四个。在几乎所有的来源的光发射也可以归因于未解决的，老星团的质量10 7 10 8 M。我们发现吸积率和喷流功率之间的相关性和射电响度和吸积率之间的反相关性的证据。我们确认以前的研究结果，无线电发射是严重低估了ADAF模型和解释的相对论喷流。我们发现的证据之间的非线性关系的X射线和测热光度和轻微的红外过量的平均模型SED相比，类星体。我们认为，硬度的X射线光谱可以用来识别X射线发射机制和讨论的方向，在理解的X射线的起源进展。
We perform an exploratory study of the physical properties of accretion ows and jets in low-luminosity active galactic nuclei (LLAGNs) by modeling the spectral energy distributions (SEDs) of 12 LLAGNs in low-ionization nuclear emission-line regions (LINERs). These SEDs we constructed from high-resolution radio, X-ray and optical/UV observations of the immediate vicinity of the black hole. We adopt a coupled accretion-jet model comprising an inner advection-dominated accretion ow (ADAF) and an outer standard thin disk. We present best-t models in which either the ADAF or the jet dominate the X-ray emission. Six sources in our sample display an opticalUV excess with respect to ADAF and jet models; this excess can be explained as emission from the truncated disk with transition radii 30 225 RS in four of them. In almost all sources the optical emission can also be attributed to unresolved, old stellar clusters with masses 10 7 10 8 M . We nd evidence for a correlation between the accretion rate and jet power and an anti-correlation between the radio-loudness and the accretion rate. We conrm previous ndings that the radio emission is severely underpredicted by ADAF models and explained by the relativistic jet. We nd evidence for a nonlinear relation between the X-ray and bolometric luminosities and a slight IR excess in the average model SED compared to that of quasars. We suggest that the hardness of the X-ray spectrum can be used to identify the X-ray emission mechanism and discuss directions for progress in understanding the origin of the X-rays.