论文标题
观察性提示通过Nustar数据通过X射线掩盖气体行为
Observational hints on the torus obscuring gas behaviour through X-rays with NuSTAR data
论文作者
论文摘要
根据理论，活性银河核（AGN）的圆环是从积聚磁盘上的风中维持的，对于低有效的AGN，已经提出这种结构消失了。但是，其消失的确切条件尚不清楚。这可以在X射线的整个反射分量中进行研究，X射线与隔离的AGN中圆环的内壁处的远处和中性物质有关。我们选择一个用nustar观察到的81个AGN的样品，距离为d <200 \，MPC和Eddington Rate $ \ rm {λ_{eDd} \ equiv l_ {bol}/l_ {bol}/l_ {edd} <10^{ - 3}}} $。我们使用模型占部分覆盖的吸收剂以及中性材料的反射成分的模型拟合3-70 \ keV光谱。我们发现，反射成分的存在跨越了各种黑洞质量和侧射仪，只有$ \ sim $ 13 \％的样本（11来源）缺乏任何反射特征。这些来源落在L-MBH图中可能缺少圆环的区域。对于具有检测到的反射组件的来源，我们发现其中绝大多数是高度遮盖的（$ \ rm {\ log \ n_h> 23} $），其中$ \ rm {\ rm {\ sim 20 \％} $是compton-thick。我们还发现，无扫描源的数量增加，并在$ \ rm {fekα} $排放线和compton-hump Luminosisities之间的比率增加到$ \ rm {λ_{eDd} = 10^{ - 5}} $，这表明该贡献了$ \ rm rm rm rm rm {fekα}的贡献。
According to theory, the torus of active galactic nuclei (AGN) is sustained from a wind coming off the accretion disk, and for low efficient AGN, it has been proposed that such structure disappears. However, the exact conditions for its disappearance remain unclear. This can be studied throughout the reflection component at X-rays, which is associated with distant and neutral material at the inner walls of the torus in obscured AGN. We select a sample of 81 AGNs observed with NuSTAR with a distance limit of D< 200\,Mpc and Eddington rate $\rm{λ_{Edd} \equiv L_{bol}/L_{Edd}<10^{-3}}$. We fit the 3-70\,keV spectra using a model accounting for a partial-covering absorber plus a reflection component from neutral material. We find that the existence of the reflection component spans in a wide range of black-hole mass and bolometric luminosities, with only $\sim$13\% of our sample (11 sources) lacking of any reflection signatures. These sources fall in the region in which the torus may be lacking in the L-MBH diagram. For the sources with a detected reflection component, we find that the vast majority of them are highly obscured ($\rm{\log \ N_H > 23}$), with $\rm{\sim 20\%}$ being Compton-thick. We also find an increase on the number of unobscured sources and a tentative increase on the ratio between $\rm{FeKα}$ emission line and Compton-hump luminosities toward $\rm{λ_{Edd}=10^{-5}}$, suggesting that the contribution of the $\rm{FeKα}$ line changes with Eddington ratio.
