论文标题
NGC 7212的Chandra观测:大规模扩展硬X射线排放
Chandra Observations of NGC 7212: Large-scale Extended Hard X-ray Emission
论文作者
论文摘要
Recent observations of nearby Compton thick (CT) active galactic nuclei (AGNs) with Chandra have resolved hard (>3 keV) X-ray emission extending out from the central supermassive black hole to kiloparsec scales, challenging the long-held belief that the characteristic hard X-ray continuum and fluorescent Fe K lines originate in the inner ~parsec due to the excitation of obscuring material.在本文中,我们介绍了NGC 7212的最新Chandra ACIS-S观察结果,即紧凑型相互作用星系中的CT AGN,总有效暴露约为150 ks。我们发现在中央〜千乘积之外发现了约20%的观察到的发射,与软X射线相关,约有17%,而硬X射线连续体和Fe K系列约为3%。该发射沿电离锥和交叉方向延伸至〜3.8 kpc尺度。 NGC 7212的光谱最好由热和光电离模型的混合物表示,这些模型表明存在复杂的气体相互作用。这些观察结果与其他CT AGN(例如ESO 428-G014,NGC 1068)中观察到的观察结果一致,提供了进一步的证据表明这可能是一种常见现象。扩展CT AGN的高分辨率观察为了解AGN反馈如何影响宿主星系对银河尺度的影响提供了一个特别有价值的环境。
Recent observations of nearby Compton thick (CT) active galactic nuclei (AGNs) with Chandra have resolved hard (>3 keV) X-ray emission extending out from the central supermassive black hole to kiloparsec scales, challenging the long-held belief that the characteristic hard X-ray continuum and fluorescent Fe K lines originate in the inner ~parsec due to the excitation of obscuring material. In this paper we present the results of the most recent Chandra ACIS-S observations of NGC 7212, a CT AGN in a compact group of interacting galaxies, with a total effective exposure of ~150 ks. We find ~20 percent of the observed emission is found outside of the central ~kiloparsec, with ~17 percent associated with the soft X-rays, and ~3 percent with hard X-ray continuum and Fe K line. This emission is extended both along the ionization cone and in the cross-cone direction up to ~3.8 kpc scales. The spectrum of NGC 7212 is best represented by a mixture of thermal and photoionization models that indicate the presence of complex gas interactions. These observations are consistent with what is observed in other CT AGN (e.g., ESO 428-G014, NGC 1068), providing further evidence that this may be a common phenomenon. High-resolution observations of extended CT AGN provide an especially valuable environment for understanding how AGN feedback impacts host galaxies on galactic scales.