Galaxy mergers in EAGLE do not induce a significant amount of black hole growth yet do increase the rate of luminous AGN

Show full item record



Permalink

http://hdl.handle.net/10138/320657

Citation

McAlpine , S , Harrison , C M , Rosario , D J , Alexander , D M , Ellison , S L , Johansson , P H & Patton , D R 2020 , ' Galaxy mergers in EAGLE do not induce a significant amount of black hole growth yet do increase the rate of luminous AGN ' , Monthly Notices of the Royal Astronomical Society , vol. 494 , no. 4 , pp. 5713-5733 . https://doi.org/10.1093/mnras/staa1123

Title: Galaxy mergers in EAGLE do not induce a significant amount of black hole growth yet do increase the rate of luminous AGN
Author: McAlpine, Stuart; Harrison, Chris M.; Rosario, David J.; Alexander, David M.; Ellison, Sara L.; Johansson, Peter H.; Patton, David R.
Other contributor: University of Helsinki, Particle Physics and Astrophysics
University of Helsinki, Particle Physics and Astrophysics

Date: 2020-06
Language: eng
Number of pages: 21
Belongs to series: Monthly Notices of the Royal Astronomical Society
ISSN: 0035-8711
DOI: https://doi.org/10.1093/mnras/staa1123
URI: http://hdl.handle.net/10138/320657
Abstract: We investigate the connection between galaxy-galaxy mergers and enhanced black hole (BH) growth using the cosmological hydrodynamical EAGLE simulation. We do this via three methods of analysis, investigating: the merger fraction of AGN, the AGN fraction of merging systems, and the AGN fraction of galaxies with close companions. In each case, we find an increased abundance of AGN within merging systems relative to control samples of inactive or isolated galaxies (by up to a factor of approximate to 3 depending on the analysis method used), confirming that mergers are enhancing BH accretion rates for at least a subset of the galaxy population. The greatest excess of AGN triggered via a merger are found in lower mass (M-* similar to 10(10) M-circle dot) gas rich (f(gas) > 0.2) central galaxies with lower mass BHs (M-BH similar to 10(7) M-circle dot) at lower redshifts (z <1). We find no enhancement of AGN triggered via mergers in more massive galaxies (M-* greater than or similar to 10(11) M-circle dot). The enhancement of AGN is not uniform throughout the phases of a merger, and instead peaks within the early remnants of merging systems (typically lagging approximate to 300 Myr post-coalescence of the two galaxies at z = 0.5). We argue that neither major (M-*,M-1/M-*,M-2 = 1/4) nor minor mergers (1/10 <M-*,M-1/M-*,M-2 <1/4) are statistically relevant for enhancing BH masses globally. Whilst at all redshifts the galaxies experiencing a merger have accretion rates that are on average 2-3 times that of isolated galaxies, the majority of mass that is accreted on to BHs occurs outside the periods of a merger. We compute that on average no more than 15 per cent of a BHs final day mass comes from the enhanced accretion rates triggered via a merger.
Subject: galaxies: active
galaxies: evolution
galaxies: formation
galaxies: high-redshift
galaxies: interactions
DIGITAL SKY SURVEY
STAR-FORMATION
COSMOLOGICAL SIMULATIONS
HOST GALAXIES
STELLAR MASSES
MAJOR MERGERS
EVOLUTION
PAIRS
QUASARS
LUMINOSITIES
115 Astronomy, Space science
Rights:


Files in this item

Total number of downloads: Loading...

Files Size Format View
staa1123.pdf 8.563Mb PDF View/Open
2002.00959.pdf 4.601Mb PDF View/Open

This item appears in the following Collection(s)

Show full item record