Supermassive black holes in cosmological simulations I: M_BH-M_star relation and black hole mass function

Melanie Habouzit; Yuan Li; Rachel S. Somerville; Shy Genel; Annalisa Pillepich; Marta Volonteri; Romeel Davé; Yetli Rosas-Guevara; Stuart McAlpine; Sébastien Peirani; Lars Hernquist; Daniel Anglés-Alcázar; Amy Reines; Richard Bower; Yohan Dubois; Dylan Nelson; Christophe Pichon; Mark Vogelsberger

doi:10.1093/mnras/stab496

arXiv · 2006.10094

Supermassive black holes in cosmological simulations I: M_BH-M_star relation and black hole mass function

Melanie Habouzit·Yuan Li·Rachel S. Somerville·Shy Genel·Annalisa Pillepich·Marta Volonteri·Romeel Davé·Yetli Rosas-Guevara·Stuart McAlpine·Sébastien Peirani·Lars Hernquist·Daniel Anglés-Alcázar·Amy Reines·Richard Bower·Yohan Dubois·Dylan Nelson·Christophe Pichon·Mark Vogelsberger

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Abstract

The past decade has seen significant progress in understanding galaxy formation and evolution using large-scale cosmological simulations. While these simulations produce galaxies in overall good agreement with observations, they employ different sub-grid models for galaxies and supermassive black holes (BHs). We investigate the impact of the sub-grid models on the BH mass properties of the Illustris, TNG100, TNG300, Horizon-AGN, EAGLE, and SIMBA simulations, focusing on the M_BH-M_star relation and the BH mass function. All simulations predict tight M_BH-M_star relations, and struggle to produce the lowest (M_BH< 10^7.5 Msun) in galaxies of M_star~10^10.5-10^11.5 Msun. While the time evolution of the mean M_BH-M_star relation is mild (<1 dex in BH mass for 0 10^9 Msun in most of the simulations. The BH mass function is dominated by efficiently accreting BHs (log10 f_Edd >-2$) at high redshifts, and transitions progressively from the high-mass to the low-mass end to be governed by inactive BHs. The transition time and the contribution of active BHs are different among the simulations, and can be used to evaluate models against observations.

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Melanie Habouzit, Yuan Li, Rachel S. Somerville, Shy Genel, Annalisa Pillepich, Marta Volonteri, Romeel Davé, Yetli Rosas-Guevara, Stuart McAlpine, Sébastien Peirani, Lars Hernquist, Daniel Anglés-Alcázar, Amy Reines, Richard Bower, Yohan Dubois, Dylan Nelson, Christophe Pichon, Mark Vogelsberger. 2020-06-17. Supermassive black holes in cosmological simulations I: M_BH-M_star relation and black hole mass function. https://doi.org/10.1093/mnras/stab496

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