2017/03/14 by Guinevere Kauffmann, Dylan Nelson, Brice Ménard +2 · 11 citations
Physics and Astronomy · #Active galactic nucleus #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Dark matter #Dark matter halo #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy formation and evolution #Halo #Physics #Quasar #RADIUS #Redshift #Stellar, planetary, and galactic studies #Velocity dispersion #Virial theorem #astro-ph.GA
paper · pdf · doi:10.1093/mnras/stx639
published in Monthly Notices of the Royal Astronomical Society 468(3), 3737-3745 (Oxford University Press) · 10 pages, 11 figures, accepted in MNRAS
arxiv created 2017/03/14 · openalex publication_date 2017/03/14 · arxiv updated 2017/05/10 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We use the latest version of the metal line absorption catalogue of Zhu & Ménard to study the clustering of Mg ii absorbers around massive galaxies (∼1011.5 M⊙), quasars and radio-loud active galactic nuclei (AGNs) with redshifts between 0.4 and 0.75. Clustering is evaluated in two dimensions by binning absorbers both in the projected radius and velocity separation. Excess Mg ii is detected around massive galaxies out to Rp = 20 Mpc. At projected radii less than 800 kpc, the excess extends out to velocity separations of 10 000 km s−1. The extent of the high-velocity tail within this radius is independent of the mean stellar age of the galaxy and whether or not it harbours an AGN. We interpret our results using the publicly available Illustris and Millennium simulations. Models where the Mg ii absorbers trace the dark matter particle or subhalo distributions do not fit the data. They overpredict the clustering on small scales and do not reproduce the excess high velocity separation Mg ii absorbers seen within the virial radius of the halo. The Illustris simulations that include thermal, but not mechanical feedback from AGNs, also do not provide an adequate fit to the properties of the cool halo gas within the virial radius. We propose that the large velocity separation Mg ii absorbers trace gas that has been pushed out of the dark matter haloes, possibly by multiple episodes of AGN-driven mechanical feedback acting over long time-scales.