3 years ago

# Cosmic evolution of stellar quenching by AGN feedback: clues from the Horizon-AGN simulation.

C. Pichon, S. Peirani, J. Devriendt, M. Volonteri, S. Kaviraj, R. S. Beckmann, N. E. Chisari, A. Slyz, Y. Dubois, C. Laigle, M. L. A. Richardson

The observed massive end of the galaxy stellar mass function is steeper than its predicted dark matter halo counterpart in the standard $\Lambda$CDM paradigm. In this paper, we investigate the impact of active galactic nuclei (AGN) feedback on star formation in massive galaxies. We isolate the impact of AGNs by comparing two simulations from the HORIZON suite, which are identical except that one also includes super massive black holes (SMBH), and related feedback models. This allows us to cross-identify individual galaxies between simulations and quantify the effect of AGN feedback on their properties, including stellar mass and gas outflows. We find that massive galaxies ($\rm M_{*} \geq 10^{11} M_\odot$) are quenched by AGN feedback to the extent that their stellar masses decrease by up to 80% at $z=0$. SMBHs affect their host halo through a combination of outflows that reduce their baryonic mass, particularly for galaxies in the mass range $\rm 10^9 M_\odot \leq M_{*} \leq 10^{11} M_\odot$, and a disruption of central gas inflows, which limits in-situ star formation. As a result, net gas inflows onto massive galaxies, $\rm M_{*} \geq 10^{11} M_\odot$, drop by up to 70%. We measure a redshift evolution in the stellar mass ratio of twin galaxies with and without AGN feedback, with galaxies of a given stellar mass showing stronger signs of quenching earlier on. This evolution is driven by a progressive flattening of the $\rm M_{\rm SMBH}-M_*$ relation with redshift, particularly for galaxies with $\rm M_{*} \leq 10^{10} M_\odot$. $\rm M_{\rm SMBH}/M_*$ ratios decrease over time, as falling average gas densities in galaxies curb SMBH growth.

Publisher URL: http://arxiv.org/abs/1701.07838

DOI: arXiv:1701.07838v2

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.