Early-type galaxy density profiles from IllustrisTNG: II. Evolutionary trend of the total density profile

Abstract

We study the evolutionary trend of the total density profile of early-type galaxies (ETGs) in IllustrisTNG. To this end, we trace ETGs from $z=0$ to $z=4$ and measure the power-law slope ${\gamma }^{\prime }$ of the total density profile for their main progenitors. We find that their ${\gamma }^{\prime }$ steepen on average during $z\sim 4-2$, then becoming shallower until $z=1$, after which they remain almost constant, aside from a residual trend of becoming shallower towards $z=0$. We also compare to a statistical sample of ETGs at different redshifts, selected based on their luminosity profiles and stellar masses. Due to different selection effects, the average slopes of the statistical samples follow a modified evolutionary trend. They monotonically decrease since $z=3$, and after $z\approx 1$, they remain nearly invariant with a mild increase towards $z=0$. These evolutionary trends are mass-dependent for both samples, with low-mass galaxies having in general steeper slopes than their more massive counterparts. Galaxies that transitioned to ETGs more recently have steeper mean slopes as they tend to be smaller and more compact at any given redshift. By analyzing the impact of mergers and AGN feedback on the progenitors' evolution, we conjecture a multi-phase path leading to isothermality in ETGs: dissipation associated with rapid wet mergers tends to steepen ${\gamma }^{\prime }$ from $z=4$ to $z=2$, whereas subsequent AGN feedback (especially in the kinetic mode) makes ${\gamma }^{\prime }$ shallower again from $z=2$ to $z=1$. Afterwards, passive evolution from $z=1$ to $z=0$, mainly through gas-poor mergers, mildly decreases ${\gamma }^{\prime }$ and maintains the overall mass distribution close to isothermal.

19 pages, 8 figures, 4 tables. Accepted for publication in MNRAS, updated to match published version

References in corpus (40)

• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• Introducing the Illustris Project: Simulating the coevolution of dark and visible matter in the Universe
• Cold streams in early massive hot haloes as the main mode of galaxy formation
• Overview of the SDSS-IV MaNGA Survey: Mapping Nearby Galaxies at Apache Point Observatory
• The hierarchical formation of the brightest cluster galaxies
• The EAGLE simulations of galaxy formation: calibration of subgrid physics and model variations
• Properties of galaxies reproduced by a hydrodynamic simulation
• Simulating galaxy formation with black hole driven thermal and kinetic feedback
• Introducing the Illustris Project: the evolution of galaxy populations across cosmic time
• A unified model for AGN feedback in cosmological simulations of structure formation
• The Illustris simulation: the evolving population of black holes across cosmic time
• Compaction and Quenching of High-z Galaxies in Cosmological Simulations: Blue and Red Nuggets
• Structure and star formation in galaxies out to z=3: evidence for surface density dependent evolution and upsizing
• The Structure & Dynamics of Massive Early-type Galaxies: On Homology, Isothermality and Isotropy inside one Effective Radius
• The Size Evolution of Star-forming and Quenched Galaxies in the IllustrisTNG simulation
• The dark nemesis of galaxy formation: why hot haloes trigger black hole growth and bring star formation to an end
• The Formation of Massive, Compact Galaxies at z=2 in the Illustris Simulation
• Black Holes on FIRE: Stellar Feedback Limits Early Feeding of Galactic Nuclei
• Equal- and unequal-mass mergers of disk and elliptical galaxies with black holes
• The Redshift Evolution of Wet, Dry, and Mixed Galaxy Mergers from Close Galaxy Pairs in the DEEP2 Galaxy Redshift Survey
• Galaxy growth in the concordance $\Lambda$CDM cosmology
• Galactic Angular Momentum in the Illustris Simulation: Feedback and the Hubble Sequence
• The impact of feedback on cosmological gas accretion
• Predicting Quiescence: The Dependence of Specific Star Formation Rate on Galaxy Size and Central Density at 0.5<z<2.5
• Two Conditions for Galaxy Quenching: Compact Centres and Massive Haloes
• The SL2S Galaxy-scale Lens Sample. II. Cosmic evolution of dark and luminous mass in early-type galaxies
• The impact of galactic properties and environment on the quenching of central and satellite galaxies: A comparison between SDSS, Illustris and L-Galaxies
• The MASSIVE Survey - V. Spatially-Resolved Stellar Angular Momentum, Velocity Dispersion, and Higher Moments of the 41 Most Massive Local Early-Type Galaxies
• The Sloan Lens ACS Survey. XIII. Discovery of 40 New Galaxy-Scale Strong Lenses
• Small scatter and nearly-isothermal mass profiles to four half-light radii from two-dimensional stellar dynamics of early-type galaxies
• The Sloan Lens ACS Survey. XII. Extending Strong Lensing to Lower Masses
• The uniformity and time-invariance of the intra-cluster metal distribution in galaxy clusters from the IllustrisTNG simulations
• The Effect of the AGN Feedback on the Interstellar Medium of Early-Type Galaxies: 2D Hydrodynamical Simulations of the Low-Rotation Case
• Systematic trends in total-mass profiles from dynamical models of early-type galaxies
• Systematic variations of central mass density slopes in early-type galaxies
• The origin and properties of massive prolate galaxies in the Illustris simulation
• Evolution of central dark matter of early-type galaxies up to z ~ 0.8
• Two-component galaxies with flat rotation curve
• Reducing biases on $H_0$ measurements using strong lensing and galaxy dynamics: results from the EAGLE simulation
• Mass density slope of elliptical galaxies from strong lensing and resolved stellar kinematics

Cited by in corpus (6)

• Hubble Asteroid Hunter: II. Identifying strong gravitational lenses in HST images with crowdsourcing
• Total mass density slopes of early-type galaxies using Jeans dynamical modelling at redshifts $0.29<z<0.55$
• Survey2Survey: A deep learning generative model approach for cross-survey image mapping
• AGEL: Is the Conflict Real? Investigating Galaxy Evolution Models using Strong Lensing at 0.3 < z < 0.9
• Comparing Lensing and Stellar Orbital Models of a Nearby Massive Strong-Lens Galaxy
• Simulation-guided galaxy evolution inference: A case study with strong lensing galaxies