The evolution of low-mass central galaxies in the vicinity of massive structures and its impact on the two-halo conformity

Abstract

We investigated the population of low-mass central galaxies with Mstar = $10^{9.5}-10^{10}$ Msun/h, inhabiting regions near massive groups and clusters of galaxies using the TNG300 and MDPL2-SAG simulations. We set out to study their evolutionary histories, aiming to find hints about the large-scale conformity signal they produce. We also used a control sample of central galaxies with the same stellar mass range located far away from massive structures. For both samples, we find a subpopulation of galaxies accreted by another halo in the past, but now considered central galaxies; we refer to these objects as former satellites. The number of former satellites is higher for quenched central galaxies near massive systems, with fractions of 45% and 17% in TNG300 and MDPL2-SAG. Our results in TNG300 show that former satellites pollute the sample of central galaxies because they suffered environmental processes when they were satellites hosted typically by massive dark matter halos (M200 $\ge 10^{13}$ Msun/h) since z$\lesssim$0.5. After removing former satellites, the evolutionary trends for quenched central galaxies near massive structures are fairly similar to those of the quenched control galaxies, showing small differences at low redshift. For MDPL2-SAG instead, former satellites were hosted by less massive halos, with a mean halo mass around $10^{11.4}$ Msun/h, and the evolutionary trends remain equal before and after removing former satellite galaxies. We also measured the two-halo conformity, i.e, the correlation in the sSFR between low-mass central galaxies and their neighbors at Mpc scales, and how former satellites contribute to the signal at three different redshifts: z=0, 0.3, and 1. The time evolution of the conformity signal in the simulations presents apparent contradictory results: it decreases from z=0 to z=1 in MDPL2-SAG, while it increases in TNG300 (abridged).

17 pages, 11 figures. Published in A&A

References in corpus (20)

• Simulating galaxy formation with black hole driven thermal and kinetic feedback
• Strangulation as the primary mechanism for shutting down star formation in galaxies
• Ram pressure stripping the hot gaseous halos of galaxies in groups and clusters
• LoCuSS: The slow quenching of star formation in cluster galaxies and the need for pre-processing
• Cold gas stripping in satellite galaxies: from pairs to clusters
• Environmental Dependence of Cold Dark Matter Halo Formation
• The Three Hundred Project: Backsplash galaxies in simulations of clusters
• Ram pressure stripping in a galaxy formation model. I. A novel numerical approach
• MultiDark-Galaxies: data release and first results
• Convergence properties of halo merger trees; halo and substructure merger rates across cosmic history
• The Role of Groups in Galaxy Evolution: compelling evidence of pre-processing out to the turnaround radius of clusters
• Simulating the evolution of disc galaxies in a group environment. II. The influence of close-encounters between galaxies
• The Physical Origin of Galactic Conformity: From Theory to Observation
• On the environmental influence of groups and clusters of galaxies beyond the virial radius: Galactic conformity at few Mpc scales
• The Three Hundred project: Galaxy groups do not survive cluster infall
• Leavers and remainers: Galaxies split by group-exit
• The Three Hundred project: connection between star formation quenching and dynamical evolution in and around simulated galaxy clusters
• Pre- and post-processing of cluster galaxies out to $5\times R_{200}$: The extreme case of A2670
• Dissect two-halo galactic conformity effect for central galaxies: The dependence of star formation activities on the large-scale environment
• Backsplash galaxies and their impact on galaxy evolution: a three-stage, four-type perspective

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