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arXiv · 2003.07365

Contribution of Flares from Tidal Disruption of Stars to high-redshift AGN

Hamsa Padmanabhan·Abraham Loeb
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Abstract

We explore the contributions of Tidal Disruption Events (TDEs) to the flares in Active Galactic Nuclei (AGN) at high redshifts. Using the latest data available from X-ray and optical observations of high-redshift galaxies, in combination with the evolution of their central supermassive black holes, we calculate the contribution of TDE to AGNs as a function of their luminosities. We find that at low redshifts ($z < 1$), a few percent of all AGN with bolometric luminosities $L_{\rm Bol} \lesssim 10^{44}$ erg s$^{-1}$ may be attributable to possible TDEs. However, this fraction can significantly increase at earlier cosmic times, including up to several tens of percent of the population of AGN at $z \gtrsim 3$. TDEs may comprise a significant fraction of the Compton-Thick (CT) AGN population at $z \gtrsim 3$. The above findings motivate further calibration with upcoming X-ray missions and spectroscopic surveys targeting TDE-AGN.

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Hamsa Padmanabhan, Abraham Loeb. 2020-03-16. Contribution of Flares from Tidal Disruption of Stars to high-redshift AGN. https://doi.org/10.1051/0004-6361/202040273

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