论文标题
IRAS 17020+4544的X射线超快速流出的紫外线对应物
UV counterpart of an X-ray ultra-fast outflow in IRAS 17020+4544
论文作者
论文摘要
我们报告发现在狭窄的Seyfert-1 Galaxy IRAS 17020+4544中发现低离子X射线超快速流出（UFO）的UV吸收对应物。这种UFO的紫外线标志被视为远处频谱中的狭窄而蓝光的Lyman-Alpha吸收特征，在哈勃太空望远镜（HST）上用宇宙起源光谱仪（COS）摄入。发现Lyman -Alpha特征的流出速度为-23430 km/s（0.078 C）。我们进行了高分辨率的紫外线光谱和光电离模型，以研究在HTS/COS光谱中看到的UFO。我们的建模结果表明，UV UFO对应于先前使用XMM-Newton的反射光谱仪（RGS）发现的X射线UFO的低离子化，低速分量。 X射线UFO的其他高速和高电离成分在HST/COS频谱中未显着检测到与我们的光电离计算的预测一致。 IRAS 17020+4544中不明飞行物的多元电离和速度成分提出了一种场景，其中强大的主要不明飞行物进入并震惊了环境介质，从而形成了较弱的次级UFO组件，例如在UV频段中发现的一个。
We report on the discovery of a UV absorption counterpart of a low-ionization X-ray ultra-fast outflow (UFO) in the Narrow-Line Seyfert-1 galaxy IRAS 17020+4544. This UV signature of the UFO is seen as a narrow and blueshifted Lyman-alpha absorption feature in the far-UV spectrum, taken with the Cosmic Origins Spectrograph (COS) on the Hubble Space Telescope (HST). The Lyman-alpha feature is found to be outflowing with a velocity of -23430 km/s (0.078 c). We carry out high-resolution UV spectroscopy and photoionization modeling to study the UFO that is seen in the HTS/COS spectrum. The results of our modeling show that the UV UFO corresponds to a low-ionization, low-velocity component of the X-ray UFO found previously with XMM-Newton's Reflection Grating Spectrometer (RGS). The other higher-velocity and higher-ionization components of the X-ray UFOs are not significantly detected in the HST/COS spectrum, consistent with predictions of our photoionization calculations. The multiple ionization and velocity components of the UFOs in IRAS 17020+4544 suggest a scenario where a powerful primary UFO entrains and shocks the ambient medium, resulting in formation of weaker secondary UFO components, such as the one found in the UV band.
