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arXiv · 2411.02270

Connecting dust and outflows in AGN: the intriguing case of NGC 6860

Ioanna Psaradaki·Missagh Mehdipour·Daniele Rogantini·Elisa Costantini·Norbert Schulz·Sascha Zeegers·Eleonora Caruso
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Abstract

Cosmic dust plays a crucial role in the evolution of galaxies, significantly influencing star formation and the interstellar medium. However, in active galactic nuclei (AGN), the role and origin of dust remain poorly understood. High-resolution X-ray spectroscopy is a powerful tool for probing the properties of dust in AGN. NGC 6860, an X-ray bright type-1 quasar, is an ideal target for investigating the connection between dust and winds in AGN. It exhibits reddening and X-ray absorption by both dust and winds. By modeling high-resolution X-ray spectra from XMM-Newton and Chandra observations, we determine the properties of dust and outflows in this AGN. Our analysis finds four photoionized components, outflowing with velocities of 50-300 km/s. The first two are relatively highly ionized with logxi = 3.4 and logxi = 2.9. The results of our photoionization modeling suggest that these two components are thermally unstable. The third component is ionized, with logxi = 2.3 and is located further away from the central black hole. The fourth component is less ionized, and is possibly located in the host galaxy. The application of dust models enables us to probe the abundance and location of the dust in NGC 6860. Our findings suggest that dust absorption and reddening originates from the extended narrow-line region and its host galaxy.

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Ioanna Psaradaki, Missagh Mehdipour, Daniele Rogantini, Elisa Costantini, Norbert Schulz, Sascha Zeegers, Eleonora Caruso. 2025-02-07. Connecting dust and outflows in AGN: the intriguing case of NGC 6860. https://arxiv.org/abs/2411.02270

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