论文标题
超柔软的窄线seyfert 1星系的光盘反射模型
A Disc Reflection Model for Ultra-Soft Narrow-Line Seyfert 1 Galaxies
论文作者
论文摘要
我们对五个狭窄的Seyfert 1星系（NLS1）的XMM-Newton观测值进行了详细分析。它们都在X射线频带中显示出非常柔软的连续发射，其光子指数为$γ\ gtrsim 2.5 $。因此，在本文中，它们被称为“ Ultra-Soft” NLS1。通过使用基于反射的模型对其光学/UV-X射线光谱分布（SED）进行建模，我们发现这些超柔软的NLS1中的盘表面的电离状态比其他典型的Seyfert 1 AGN更高。我们最适合的SED型号表明，这五个Ultra Soft NLS1的Eddington比率为$λ_ {\ rm EDD} = 1-20 $，假设可用的黑洞质量测量值。此外，我们的模型推断出这些超柔软的NLS1中的圆盘能量的很大一部分以非热发射的形式辐射出来，而不是圆盘的热发射。由于它们的极端特性，对铁带中这些来源的X射线观察特别具有挑战性。未来的观察，例如从雅典娜（Athena），将使我们能够更清晰地了解铁带中的光谱形状，从而将反射模型与对其宽带光谱的其他解释区分开。
We present a detailed analysis of the XMM-Newton observations of five narrow-line Seyfert 1 galaxies (NLS1s). They all show very soft continuum emission in the X-ray band with a photon index of $Γ\gtrsim 2.5$. Therefore, they are referred to as `ultra-soft' NLS1s in this paper. By modeling their optical/UV-X-ray spectral energy distribution (SED) with a reflection-based model, we find indications that the disc surface in these ultra-soft NLS1s is in a higher ionisation state than other typical Seyfert 1 AGN. Our best-fit SED models suggest that these five ultra-soft NLS1s have an Eddington ratio of $λ_{\rm Edd}=1-20$ assuming available black hole mass measurements. In addition, our models infer that a significant fraction of the disc energy in these ultra-soft NLS1s is radiated away in the form of non-thermal emission instead of the thermal emission from the disc. Due to their extreme properties, X-ray observations of these sources in the iron band are particularly challenging. Future observations, e.g. from Athena, will enable us to have a clearer view of the spectral shape in the iron band and thus distinguish the reflection model from other interpretations of their broadband spectra.
