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Dynamical and Spectral Modeling of the Ionized Gas and Nuclear Environment in NGC 3783

Doron Chelouche·Hagai Netzer
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Abstract

We present a new approach for calculating the physical properties of highly ionized X-ray flows in active galactic nuclei (AGN). Our method relies on a detailed treatment of the structure, dynamics and spectrum of the gas. A quantitative comparison of our model predictions with the 900 ksec Chandra/HETG X-ray spectrum of NGC 3783 shows that: (1) The highly ionized outflow is driven by thermal pressure gradients and radiation pressure force is less important. (2) A full featured dynamical model that provides a very good fit to the high resolution X-ray spectrum requires a multi-phased flow with a density power spectrum reminiscent of the interstellar medium. (3) Adiabatic cooling is an important factor and so is an additional heating source that may be related to the apparent multi-phase and turbulent nature of the flow. (4) The base of the flow is ~1pc from the central object, in agreement with some, but not all previous estimates. (5) The mass loss rate is in the range 0.01-0.1 solar masses per year which is smaller than previous estimates and of the same order of the mass accretion rate in this object.

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Doron Chelouche, Hagai Netzer. 2005-02-14. Dynamical and Spectral Modeling of the Ionized Gas and Nuclear Environment in NGC 3783. https://doi.org/10.1086/429580

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