论文标题
维持活性银河核积聚圆盘中的温暖电晕
Sustaining a Warm Corona in Active Galactic Nuclei Accretion Discs
论文作者
论文摘要
Warm coronae, thick ($τ_{\mathrm{T}}\approx 10$-$20$, where $τ_{\mathrm{T}}$ is the Thomson depth) Comptonizing regions with temperatures of $\sim 1$ keV, are proposed to exist at the surfaces of accretion discs in active galactic nuclei (AGNs).通过与反射光谱结合使用，温暖的冠状病因可能导致产生AGN X射线光谱中看到的光滑柔软过量。本文研究了温暖的电晕必须如何调整，以通过AGN通量的巨大变化来维持软过量。假设有照明的硬X射线幂律，气体密度，汤姆森深度和冠状加热强度随着积聚率的变化而有所不同，则计算了一维恒定密度和静水式冠状冠模型的光谱。我们确定了产生温度温度在$ 0.3 $至$ 1.1 $ $ KEV的温暖冠的模型，并在$ 0.5 $ -2 $ KEV和$ 2 $ - $ 10 $ kev bands中测量光子指数和发射通量。这些数量之间的相关性和抗相关性取决于温暖电晕的演化和结构。追踪AGN通过这些相关性遵循的路径将限制冠状冠的加热并连接到积聚盘的方式。温度结构的变化和温暖冠状的冠状加热强度将导致各种柔软的多余强度和形状。平均而言，较大的吸积率将导致温暖的电晕产生更强的软过量，这与局部塞弗特星系的观察一致。
Warm coronae, thick ($τ_{\mathrm{T}}\approx 10$-$20$, where $τ_{\mathrm{T}}$ is the Thomson depth) Comptonizing regions with temperatures of $\sim 1$ keV, are proposed to exist at the surfaces of accretion discs in active galactic nuclei (AGNs). By combining with the reflection spectrum, warm coronae may be responsible for producing the smooth soft excess seen in AGN X-ray spectra. This paper studies how a warm corona must adjust in order to sustain the soft excess through large changes in the AGN flux. Spectra from one-dimensional constant density and hydrostatic warm coronae models are calculated assuming the illuminating hard X-ray power-law, gas density, Thomson depth and coronal heating strength vary in response to changes in the accretion rate. We identify models that produce warm coronae with temperatures between $0.3$ and $1.1$ keV, and measure the photon indices and emitted fluxes in the $0.5$-$2$ keV and $2$-$10$ keV bands. Correlations and anti-correlations between these quantities depend on the evolution and structure of the warm corona. Tracing the path that an AGN follows through these correlations will constrain how warm coronae are heated and connected to the accretion disc. Variations in the density structure and coronal heating strength of warm coronae will lead to a variety of soft excess strengths and shapes in AGNs. A larger accretion rate will, on average, lead to a warm corona that produces a stronger soft excess, consistent with observations of local Seyfert galaxies.
