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Spectral Energy Distributions of Active Galactic Nuclei from an Accretion Disk with Advective Coronal Flow

T. Kawaguchi·T. Shimura·S. Mineshige
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Abstract

To explain the broad-band spectral energy distributions (SED) of Seyfert nuclei and QSOs, we study the emission spectrum emerging from a vertical disk-corona structure composed of a two-temperature plasma by solving hydrostatic equilibrium and radiative transfer self-consistently. Our model can nicely reproduce the soft X-ray excess with alpha (L_frequency proportional to the frequency to the power of -alpha) of about 1.5 and the hard tail extending to about 50 keV with alpha about 0.5. The different spectral slopes (alpha about 1.5 below 2 keV and about 0.5 above) are the results of different emission mechanisms: unsaturated Comptonization in the former and a combination of Comptonization, bremsstrahlung, and reflection of the coronal radiation at the disk-corona boundary in the latter.

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T. Kawaguchi, T. Shimura, S. Mineshige. 2000-05-08. Spectral Energy Distributions of Active Galactic Nuclei from an Accretion Disk with Advective Coronal Flow. https://doi.org/10.1016/s1387-6473(00)00077-4

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