Comparing X-ray Emission Line Fluxes of NGC 5548 to NGC 1068

Divya Patel; Maryam Dehghanian; Gary Ferland

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arXiv · 2508.13001

Comparing X-ray Emission Line Fluxes of NGC 5548 to NGC 1068

Divya Patel·Maryam Dehghanian·Gary Ferland

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Abstract

The Unification Model of AGN suggests that all AGN galaxies should exhibit similar line ratios in their spectra. NGC 5548, a Seyfert I, underwent obscuration -- similar to naturally obscured Seyfert II galaxies -- due to an outflowing accretion wind, resulting in absorption. As per the Model, a Seyfert I and a Seyfert II should show similar flux ratios during their respective obscuration states. In this note, we present a comparison of emission fluxes between NGC 5548 and NGC 1068, a Seyfert II. We present the CLOUDY prediction of NGC 5548, which underpredicts the line ratios compared to observations, likely due to SED choices. The differing observed line ratios of NGC 5548 and NGC 1068 suggest additional unknown factors in the unification model.

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Divya Patel, Maryam Dehghanian, Gary Ferland. 2025-08-18. Comparing X-ray Emission Line Fluxes of NGC 5548 to NGC 1068. https://arxiv.org/abs/2508.13001

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