Exploring variation of double-peak broad-line profile in strongly variable AGNs

Summary

The geometry and kinematics of the broad-line region (BLR) in active galactic nuclei (AGNs) are crucial for understanding supermassive black holes and AGNs. A study explores the evolution of line profiles in variable AGNs using a BLR model driven by radiation pressure on dust at the surface layers of the accretion disk.

Highlights

• The BLR model reproduces the observed anti-correlation between the peak separation of broad lines and the Eddington ratio.
• The high metallicity of Z ≳ 5Z⊙ is required to reproduce the observational anti-correlation.
• The line profile changes from double peak to single peak within several years to several decades.
• The timescale for the variation of the line profile is sensitively related to the initial or final accretion rate.
• The evolution of broad emission lines in strong variable AGNs can further test this model and shed light on BLR physics.
• The model can naturally produce single or double-peak broad lines.
• The origin of the BLR gas is regulated by the accretion process surrounding the central SMBHs.

Key Insights

• The study suggests that the BLR model can reproduce the observed anti-correlation between the peak separation of broad lines and the Eddington ratio, which is a key feature of AGNs.
• The high metallicity required to reproduce the observational anti-correlation implies that the BLR gas is enriched with heavy elements, which can provide insights into the formation and evolution of AGNs.
• The timescale for the variation of the line profile is sensitive to the initial or final accretion rate, which suggests that the BLR is a dynamic system that responds to changes in the accretion rate.
• The evolution of broad emission lines in strong variable AGNs can provide valuable information to constrain the BLR models and shed light on the physics of the BLR.
• The model's ability to naturally produce single or double-peak broad lines suggests that it can capture the complex behavior of the BLR.
• The origin of the BLR gas is regulated by the accretion process surrounding the central SMBHs, which implies that the BLR is an integral part of the AGN system.
• The study highlights the importance of considering the metallicity and accretion rate in understanding the behavior of the BLR and the evolution of AGNs.

Mindmap

Citation

Wu, J., Wu, Q., Lu, K., Cao, X., Lei, X., Wang, M., & Fan, X. (2024). Exploring variation of double-peak broad-line profile in strongly variable AGNs (Version 1). arXiv. https://doi.org/10.48550/ARXIV.2412.18146