论文标题
与钱德拉（Chandra）重新访问NGC 6240的复杂核区域
Revisiting the complex nuclear region of NGC 6240 with Chandra
论文作者
论文摘要
我们介绍了指向NGC 6240合并银河系的双重AGN的累积ACIS CHANDRA数据集的重新分析，重点是包含硬光谱连续体（5.5-5.9 keV）的硬能带，红色的fe i k alpha Line（6.0-6.4 kev）（6.0-6.4 kev）和Redssed shysed shyssed shyseven（6.0-6.4 kev）。我们已经将Chandra望远镜角度分辨率进行了完整，并且通过将飞行前校准模型与两个Bright AGN的数据进行比较，对Chandra PSF进行了建模。通过两种互补方法：（1）研究PSF减法后的残差，以及（2）通过马尔可夫链蒙特卡洛（EMC2）图像产生重建的期望，我们能够解决S AGN中从1 kpc延伸到<200 pc的结构。后者在该BH的影响力领域。我们发现在核心，N和S AGN之间的区域以及PA 120-210度的区域的2''（1 kpc）区域中，连续和Fe线的延长发射显着。从S AGN表面亮度的质心延伸至SE。扩展的Fe I Kα发射可能起源于X射线光子与密集分子云相互作用的荧光，从而对最近的高分辨率ALMA研究提供了互补的视野。在两个活动X射线核和N AGN之间，非热发射在该区域中更为普遍。我们找不到与最近针对NGC 6240提出的与第三个核有关的X射线发射的强有力的证据。
We present a reanalysis of the cumulative ACIS S Chandra data set pointed at the double AGNs of the NGC 6240 merging galaxy, focusing on the hard energy bands containing the hard spectral continuum (5.5-5.9 keV), the redshifted Fe I K alpha line (6.0-6.4 keV), and the redshifted Fe XXV line (6.4-6.7 keV). We have used to the full the Chandra telescope angular resolution, and we have modeled the Chandra PSF by comparing pre-flight calibration model to the data for the two bright AGNs. With two complementary approaches: (1) studying the residuals after PSF subtraction, and (2) producing reconstructed Expectation through Markov Chain Monte Carlo (EMC2) images, we are able to resolve structures extending from 1 kpc to <200 pc in the S AGN. The latter are within the sphere of influence of this BH. We find significant extended emission in both continuum and Fe lines in the 2'' (1 kpc) region surrounding the nuclei, in the region between the N and S AGN, and in a sector of PA 120-210 deg. extending to the SE from the centroid of the S AGN surface brightness. The extended Fe I K alpha emission is likely to originate from fluorescence of X-ray photons interacting with dense molecular clouds, providing a complementary view to recent high-resolution ALMA studies. The non-thermal emission is more prevalent in the region in between the two active X-ray nuclei, and in the N AGN. We do not find strong evidence of X-ray emission associated with the 3rd nucleus recently proposed for NGC 6240.
