论文标题
X射线耀斑中的电晕加速和冷却来自Seyfert Galaxy I ZW 1
Acceleration and cooling of the corona during X-ray flares from the Seyfert galaxy I Zw 1
论文作者
论文摘要
我们报告了X射线耀斑，这些耀斑是从1月1日由Nustar和XMM-Newton天文台观察到的活性银河核I Zwicky 1（I ZW 1）。 X射线频谱由由电晕的连续发射组成的模型很好地描述，以及其在快速旋转（> 0.94）黑洞周围的积聚盘的反射。为了对宽带光谱进行建模，有必要说明整个光盘之间电离的变化。在耀斑之前，之中和之后对X射线频谱的分析显示，与耀斑相关的电晕的基本变化。在耀斑期间，反射馏分显着下降，这与电晕的加速度一致。我们发现第一个证据表明，在X射线耀斑期间，温度从140（-20，+100）keV下降到耀斑期间的45（-9，+40）keV。铁K线的轮廓揭示了增生盘的发射率特征，表明它被紧凑的电晕照亮，在耀斑前延伸到盘上的7（-2，+4）RG延伸，但暂时证据表明，圆锥体在耀斑期间加速而膨胀。一旦耀斑消退，电晕就塌陷至6（-2，+2）Rg的半径。耀斑的快速时间表明它们在黑孔磁层内而不是在积聚盘中产生，并且电晕的变化与圆盘中种子光子的构成产生的连续体一致。
We report on X-ray flares that were observed from the active galactic nucleus I Zwicky 1 (I Zw 1) in 2020 January by the NuSTAR and XMM-Newton observatories. The X-ray spectrum is well-described by a model comprised of the continuum emission from the corona and its reflection from the accretion disc around a rapidly spinning (a > 0.94) black hole. In order to model the broadband spectrum, it is necessary to account for the variation in ionisation across the disc. Analysis of the X-ray spectrum in time periods before, during and after the flares reveal the underlying changes to the corona associated with the flaring. During the flares, the reflection fraction drops significantly, consistent with the acceleration of the corona away from the accretion disc. We find the first evidence that during the X-ray flares, the temperature drops from 140(-20,+100)keV before to 45(-9,+40)keV during the flares. The profile of the iron K line reveals the emissivity profile of the accretion disc, showing it to be illuminated by a compact corona extending no more than 7(-2,+4)rg over the disc before the flares, but with tentative evidence that the corona expands as it is accelerated during the flares. Once the flares subsided, the corona had collapsed to a radius of 6(-2,+2)rg. The rapid timescale of the flares suggests that they arise within the black-hole magnetosphere rather than in the accretion disc, and the variation of the corona is consistent with the continuum arising from the Comptonisation of seed photons from the disc.
