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arXiv · 2112.04180

Influence of Comptonization region over the ambiance of accretion disc in Active Galactic Nucleus

Abstract

Understanding the radiative and physical structures of inner region of a few 100 pc of AGNs is important to constrain the causes of their activities. Although the X-ray emission from the Comptonization region/corona and the accretion disc regulates the broad line emission regions and torus structures, the exact mutual dependency is not understood well. We performed correlation studies for X-ray, mid-infrared, and different components of Balmer emission lines for the selected sample of AGNs. Almost 10 different parameters and their inter-dependencies were explored in order to understand the underlying astrophysics. We found that the X-ray luminosity has a linear dependency on the various components of broad Balmer emission lines (e.g. L$_{\text{2-10 keV}}$ $\propto$ L$^{0.78}_{\text{H}β^{\text{B}}}$) and found a strong dependency on the optical continuum luminosity (L$_{\text{2-10 keV}}$ $\propto$ L$^{0.86}_{5100\,\textÅ}$). For a selected sample, we also observed a linear dependency between X-ray and mid-infrared luminosity (L$_{\text{2-10 keV}}$ $\propto$ L$^{0.74}_{6\,\upmu \text{m}}$). A break point was observed in our correlation studies for X-ray power-law index, $Γ$, and mass of black hole at $\sim$ log (M/M$_{\odot}$) = 8.95. Similarly the relations between $Γ$ and FWHM of H$α$ and H$β$ broad components show breaks at FWHM$_{\text{H}α}$= 7642$\pm$657 km s$^{-1}$ and FWHM$_{\text{H}β}$ = 7336$\pm$650 km s$^{-1}$. However, more data are required to confine the breaks locations exactly. We noted that $Γ$ and Eddington ratios are negatively correlated to Balmer decrements in our selected sample. We analyzed and discussed about the implications of new findings in terms of interaction AGN structures.

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K. Sriram, D. Nour, C. S. Choi. 2021-12-08. Influence of Comptonization region over the ambiance of accretion disc in Active Galactic Nucleus. https://doi.org/10.1093/mnras%2Fstab3610

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