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arXiv · 2208.01452

The Low Temperature Corona in ESO 511$-$G030 Revealed by NuSTAR and XMM-Newton

Zuobin Zhang·Jiachen Jiang·Honghui Liu·Cosimo Bambi·Christopher S. Reynolds·Andrew C. Fabian·Thomas Dauser·Kristin Madsen·Andrew Young·Luigi Gallo·Zhibo Yu·John Tomsick
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Abstract

We present the results from a coordinated XMM-Newton $+$ NuSTAR observation of the Seyfert 1 Galaxy ESO 511$-$G030. With this joint monitoring programme, we conduct a detailed variability and spectral analysis. The source remained in a low flux and very stable state throughout the observation period, although there are slight fluctuations of flux over long timescales. The broadband (0.3-78~keV) spectrum shows the presence of a power-law continuum with a soft excess below 2~keV, a relatively narrow iron K$\alpha$ emission ($\sim$6.4~keV), and an obvious cutoff at high energies. We find that the soft excess can be modeled by two different possible scenarios: a warm ($kT_{\rm e} \sim$ 0.19~keV) and optically thick ($\tau - 18\sim25$) Comptonizing corona or a relativistic reflection from a high-density ($\log [n_{\rm e}/{\rm cm}^{-3}]=17.1 \sim 18.5$) inner disc. All models require a low temperature ($kT_{\rm e} \sim$ 13~keV) for the hot corona.

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Zuobin Zhang, Jiachen Jiang, Honghui Liu, Cosimo Bambi, Christopher S. Reynolds, Andrew C. Fabian, Thomas Dauser, Kristin Madsen, Andrew Young, Luigi Gallo, Zhibo Yu, John Tomsick. 2022-08-02. The Low Temperature Corona in ESO 511$-$G030 Revealed by NuSTAR and XMM-Newton. https://doi.org/10.3847/1538-4357%2Facc38f

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