The physical drivers of gas turbulence in simulated disc galaxies

Abstract

We use the EAGLE cosmological simulations to study the evolution of the vertical velocity dispersion of cold gas, ${\sigma }_z$, in central disc galaxies and its connection to stellar feedback, gravitational instabilities, cosmological gas accretion and galaxy mergers. To isolate the impact of feedback, we analyse runs that turn off stellar and (or) AGN feedback in addition to a run that includes both. The evolution of ${\sigma }_z$ and its dependence on stellar mass and star formation rate in EAGLE are in good agreement with observations. Galaxies hosted by haloes of similar virial mass, ${\mathrm{M}}_{200}$, have similar ${\sigma }_z$ values even in runs where feedback is absent. The prevalence of local instabilities in discs is uncorrelated with ${\sigma }_z$ at low redshift and becomes only weakly correlated at high redshifts and in galaxies hosted by massive haloes. ${\sigma }_z$ correlates most strongly with the specific gas accretion rate onto the disc as well as with the degree of misalignment between the inflowing gas and the disc's rotation axis. These correlations are significant across all redshifts and halo masses, with misaligned accretion being the primary driver of high gas turbulence at redshifts $z\lesssim 1$ and for halo masses ${\mathrm{M}}_{200}\lesssim 10^{11.5}{\mathrm{M}}_{\odot }$. Galaxy mergers increase ${\sigma }_z$, but because they are rare in our sample, they play only a minor role in its evolution. Our results suggest that the turbulence of cold gas in EAGLE discs results from a complex interplay of different physical processes whose relative importance depends on halo mass and redshift.

22 pages, 12 figures. Accepted for publication in MNRAS

References in corpus (41)

• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• The EAGLE simulations of galaxy formation: calibration of subgrid physics and model variations
• The effect of photo-ionization on the cooling rates of enriched, astrophysical plasmas
• Chemical enrichment in cosmological, smoothed particle hydrodynamics simulations
• The KMOS^3D Survey: design, first results, and the evolution of galaxy kinematics from 0.7<z<2.7
• The MOSFIRE Deep Evolution Field (MOSDEF) Survey: Rest-Frame Optical Spectroscopy for ~1500 H-Selected Galaxies at 1.37 < z < 3.8
• Strongly baryon-dominated disk galaxies at the peak of galaxy formation ten billion years ago
• Clumpy Galaxies in GOODS and GEMS: Massive Analogs of Local Dwarf Irregulars
• A chronicle of galaxy mass assembly in the EAGLE simulation
• Angular momentum evolution of galaxies in EAGLE
• Resolved spectroscopy of gravitationally lensed galaxies: global dynamics and star-forming clumps on ~100pc scales
• The KMOS^3D Survey: data release and final survey paper
• Star formation quenching in simulated group and cluster galaxies: When, how, and why?
• z~2: An Epoch of Disk Assembly
• High star formation rates as the origin of turbulence in early and modern disk galaxies
• Stochastic modelling of star-formation histories II: star-formation variability from molecular clouds and gas inflow
• The KMOS Redshift One Spectroscopic Survey (KROSS): the origin of disk turbulence in z~0.9 star-forming galaxies
• GHASP : An Halpha kinematic survey of 203 spiral and irregular galaxies - VII. Revisiting the analysis of Halpha data cubes for 97 galaxies
• DYNAMO-HST Survey: Clumps in Nearby Massive Turbulent Disks and the Effects of Clump Clustering on Kiloparsec Scale Measurements of Clumps
• Hot-mode accretion and the physics of thin-disk galaxy formation
• Non-equilibrium chemistry and cooling in the diffuse interstellar medium - II. Shielded gas
• The evolution of the star formation rate function in the EAGLE simulations: A comparison with UV, IR and H$\alpha$ observations from z ~ 8 to z ~ 0
• On the evolution of galaxy spin in a cosmological hydrodynamic simulation of galaxy clusters
• Systematic difference between ionized and molecular gas velocity dispersion in $z\sim 1-2$ disks and local analogues
• Galactic inflow and wind recycling rates in the EAGLE simulations
• Structure Formation in Gas-Rich Galactic Discs with Finite Thickness: From Discs to Rings
• The impact of stellar and AGN feedback on halo-scale baryonic and dark matter accretion in the EAGLE simulations
• The SAMI Galaxy Survey: energy sources of the turbulent velocity dispersion in spatially-resolved local star-forming galaxies
• The evolution of turbulent galactic discs: gravitational instability, feedback and accretion
• The SAMI Galaxy Survey: Gas velocity dispersions in low-$z$ star-forming galaxies and the drivers of turbulence
• A thermal-kinetic subgrid model for supernova feedback in simulations of galaxy formation
• From giant clumps to clouds I: the impact of gas fraction evolution on the stability of galactic discs
• From giant clumps to clouds -- III. The connection between star formation and turbulence in the ISM
• Revealing the physical properties of gas accreting to haloes in the EAGLE simulations
• An orbital perspective on the starvation, stripping, and quenching of satellite galaxies in the EAGLE simulations
• The Origin of Exponential Star-forming Disks
• SDSS-IV MaNGA: Understanding Ionized Gas Turbulence using Integral Field Spectroscopy of 4500 Star-Forming Disk Galaxies
• Gas Accretion Can Drive Turbulence in Galaxies
• Kinematic analysis of EAGLE simulations: Evolution of ${\lambda }_{Re}$ and its connection with mergers and gas accretion
• Unveiling the main sequence of galaxies at $z\ge 5$ with the James Webb Space Telescope: predictions from simulations
• Drivers of asymmetry in synthetic H I emission-line profiles of galaxies in the EAGLE simulation

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• The ALMA-ALPAKA survey II. Evolution of turbulence in galaxy disks across cosmic time: difference between cold and warm gas
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• The ALMA-CRISTAL survey: Resolved kinematic studies of main sequence star-forming galaxies at 4<z<6
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• The AGORA High-resolution Galaxy Simulations Comparison Project. VIII: Disk Formation and Evolution of Simulated Milky Way Mass Galaxy Progenitors at $1<z<5$
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• Kennicutt-Schmidt relation of galaxies over 13 billion years in the COLIBRE hydrodynamical simulations
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