Fundamental differences in the properties of red and blue quasars: measuring the reddening and accretion properties with X-shooter
Fundamental differences in the properties of red and blue quasars: measuring the reddening and accretion properties with X-shooter
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DOI：
10.1093/mnras/stac945
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发表时间：
2022-01
影响因子：
4.8
通讯作者：
V. A. Fawcett;D. Alexander;D. Rosario;L. Klindt;E. Lusso;L. Morabito;G. Rivera
中科院分区：
文献类型：
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作者：
V. A. Fawcett;D. Alexander;D. Rosario;L. Klindt;E. Lusso;L. Morabito;G. Rivera
我们最近发现，与典型的蓝色类星体相比，红色类星体的射电性质存在根本性的差异。在这篇论文中，我们使用甚大望远镜上的X射线摄谱仪的数据，提供了40个1.45 < z < 1.65的红色和蓝色发光类星体的样本，从3000-25000 nm的光谱覆盖范围，来探索射电，发射线和吸积盘属性之间的联系。我们将各种尘埃消光曲线拟合到数据中，发现尘埃红化可以完全解释我们样本中大多数红色类星体的观测颜色，适度的消光范围为AV = 0.06-0.7 mags。我们面对我们的光谱与一个简单的薄吸积盘模型，并发现这可以描述连续的蓝色和红色类星体，一旦校正尘埃消光，我们也没有发现显着差异的吸积属性。我们在一些红色和蓝色类星体中检测到电离外流，但没有发现任何显著的证据表明它们在红色类星体中更为普遍。总的来说，我们的研究结果意味着，无线电发射更紧密地连接到环核/ISM不透明度，而不是吸积盘或流出的差异。
We have recently found fundamental differences in the radio properties of red quasars when compared to typical blue quasars. In this paper we use data from the X-shooter spectrograph on the Very Large Telescope, providing spectral coverage from ∼3000–25000 Å, of a sample of 40 red and blue luminous quasars at 1.45 < z < 1.65 to explore the connections between the radio, emission-line, and accretion-disc properties. We fit various dust-extinction curves to the data and find that dust reddening can fully explain the observed colours for the majority of the red quasars in our sample, with moderate extinctions ranging from AV ∼ 0.06–0.7 mags. We confront our spectra with a simple thin accretion-disc model and find this can describe the continua of both the blue and red quasars, once corrected for dust extinction; we also find no significant differences in the accretion properties. We detect ionized outflows in a number of red and blue quasars, but do not find any significant evidence that they are more prevalent in the red quasar population. Overall our findings imply that the radio emission is more closely connected to circumnuclear/ISM opacity rather than accretion disc or outflow differences.