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arXiv · 2609.32324

15-Year X-ray Study Links Variable Mass Accretion to Changing Look Behavior in AGN NGC 7582

Santanu Mondal·V. Jithesh·Neeraj Kumari·Tek P. Adhikari
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Abstract

Changing Look Active Galactic Nuclei (CLAGN) are a subclass of AGN that exhibit spectral state transitions in both optical/UV and X-ray bands on timescales of days to years. In this work, we studied fifteen years of X-ray data of the CLAGN NGC 7582 taken from {\it Suzaku}, {\it XMM-Newton}, and {\it NuSTAR} to understand the origin of the CL behavior. Our study reveals that the obscuration (Hydrogen column density, $N_H$) along the line of sight is associated with the failed wind scenario. The variation in mass accretion is the key that can solely explain the origin of both the failed wind and CL behavior. The mass accretion behavior in NGC 7582 resembles the hard spectral state of black hole binaries. Furthermore, the observed CL timescales in NGC 7582 can be explained either by the dynamical timescale at the BLR or by viscous and thermal timescales at the boundary layer of the corona for a black hole mass of $5.3^{+0.5}_{-0.3} \times 10^7 M_\odot$. Our study thus highlights a direct physical link between the corona and the BLR, which may be potential drivers of the CL behavior.

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Santanu Mondal, V. Jithesh, Neeraj Kumari, Tek P. Adhikari. 2026-09-26. 15-Year X-ray Study Links Variable Mass Accretion to Changing Look Behavior in AGN NGC 7582. https://arxiv.org/abs/2609.32324

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