Dynamic equilibrium sets atomic content of galaxies across cosmic time

Abstract

We analyze 88 independent high-resolution cosmological zoom-in simulations of disk galaxies in the NIHAO simulations suite to explore the connection between the atomic gas fraction and angular momentum of baryons throughout cosmic time. The study is motivated by the analytic model of \citet{obreschkow16}, which predicts a relation between the atomic gas fraction $f_{\mathrm{atm}}$ and the global atomic stability parameter $q\equiv j\sigma /(GM)$, where $M$ and $j$ are the mass and specific angular momentum of the galaxy (stars+cold gas) and $\sigma$ is the velocity dispersion of the atomic gas. We show that the simulated galaxies follow this relation from their formation ($z\simeq 4$) to present within $\sim 0.5$ dex. To explain this behavior, we explore the evolution of the local Toomre stability and find that $90\%$--$100\%$ of the atomic gas in all simulated galaxies is stable at any time. In other words, throughout the entire epoch of peak star formation until today, the timescale for accretion is longer than the timescale to reach equilibrium, thus resulting in a quasi-static equilibrium of atomic gas at any time. Hence, the evolution of $f_{\mathrm{atm}}$ depends on the complex hierarchical growth history primarily via the evolution of $q$. An exception are galaxies subject to strong environmental effects.

12 pages, 7 figures; accepted to ApJ

References in corpus (54)

• Planck 2013 results. XVI. Cosmological parameters
• How Do Galaxies Get Their Gas?
• The Star Formation Efficiency in Nearby Galaxies: Measuring Where Gas Forms Stars Effectively
• Cold dark matter haloes in the Planck era: evolution of structural parameters for Einasto and NFW profiles
• Star Formation and Feedback in Smoothed Particle Hydrodynamic Simulations--I. Isolated Galaxies
• The COS-Halos Survey: Physical Conditions and Baryonic Mass in the Low-Redshift Circumgalactic Medium
• On the evolution of the HI column density distribution in cosmological simulations
• Gaseous Galaxy Halos
• Feedback and Recycled Wind Accretion: Assembling the z=0 Galaxy Mass Function
• Making Galaxies in a Cosmological Context: The Need for Early Stellar Feedback
• The Enrichment of the Intergalactic Medium with Adiabatic Feedback I: Metal Cooling and Metal Diffusion
• The GALEX Arecibo SDSS Survey. I. Gas Fraction Scaling Relations of Massive Galaxies and First Data Release
• NIHAO project I: Reproducing the inefficiency of galaxy formation across cosmic time with a large sample of cosmological hydrodynamical simulations
• The Initial-Final Mass Relation: Direct Constraints at the Low Mass End
• The Big Problems in Star Formation: the Star Formation Rate, Stellar Clustering, and the Initial Mass Function
• The Arecibo Legacy Fast ALFA Survey: The Galaxy Population Detected by ALFALFA
• Gasoline2: A Modern SPH Code
• Cold gas stripping in satellite galaxies: from pairs to clusters
• Environmental Dependence of the Kennicutt-Schmidt Relation in Galaxies
• The GALEX Arecibo SDSS Survey. VIII. Final Data Release -- The Effect of Group Environment on the Gas Content of Massive Galaxies
• The Neutral Hydrogen Content of Galaxies in Cosmological Hydrodynamic Simulations
• Fuel Efficient Galaxies: Sustaining Star Formation with Stellar Mass Loss
• Angular momentum evolution of galaxies in EAGLE
• The Star Formation Law in Molecule-Poor Galaxies
• The EAGLE simulations: atomic hydrogen associated with galaxies
• Predictions for ASKAP Neutral Hydrogen Surveys
• The effective stability parameter for two-component galactic discs: Is 1/Q ~ 1/Q_stars + 1/Q_gas ?
• The Impact of Feedback on Disk Galaxy Scaling Relations
• Why stellar feedback promotes disc formation in simulated galaxies
• Fundamental Mass-Spin-Morphology Relation of Spiral Galaxies
• The distribution of neutral hydrogen around high-redshift galaxies and quasars in the EAGLE simulation
• A simple and accurate approximation for the Q stability parameter in multi-component and realistically thick discs
• The distribution of atomic hydrogen in EAGLE galaxies: morphologies, profiles, and HI holes
• Understanding the H2/HI Ratio in Galaxies
• Modeling the atomic-to-molecular transition in cosmological simulations of galaxy formation
• The Effect of Structure and Star Formation on the Gas Content of Nearby Galaxies
• Variation of galactic cold gas reservoirs with stellar mass
• On the Origin of the Galaxy Star-Formation-Rate Sequence: Evolution and Scatter
• The fundamental plane of star formation in galaxies revealed by the EAGLE hydrodynamical simulations
• Line Overlap and Self-Shielding of Molecular Hydrogen in Galaxies
• NIHAO X: Reconciling the local galaxy velocity function with Cold Dark Matter via mock HI observations
• The MaGICC Baryon Cycle: The Enrichment History of Simulated Disc Galaxies
• Angular Momentum Regulates Atomic Gas Fractions of Galactic Disks
• NIHAO VIII: Circum-galactic medium and outflows - The puzzles of HI and OVI gas distributions
• Dark halo response and the stellar initial mass function in early-type and late-type galaxies
• NIHAO XII: galactic uniformity in a ΛCDM universe
• Connecting and dissecting galaxies' angular momenta and neutral gas in a hierarchical universe: cue DARK SAGE
• Low Angular Momentum in Clumpy, Turbulent Disk Galaxies
• Structural and Dynamical Properties of Galaxies in a Hierarchical Universe: Sizes and Specific Angular Momenta
• The impact of environment and mergers on the HI content of galaxies in hydrodynamic simulations
• Angular momentum and local gravitational instability in galaxy discs: does $Q$ correlate with $j$ or $M$?
• NIHAO III: The constant disc gas mass conspiracy
• Revisiting the stellar mass -- angular momentum -- morphology relation: extension to higher bulge fraction, and the effect of bulge type
• The environmental dependence of neutral hydrogen in the GIMIC simulations

Cited by in corpus (9)

• Atomic hydrogen in IllustrisTNG galaxies: the impact of environment parallelled with local 21-cm surveys
• The SAMI Galaxy Survey: comparing 3D spectroscopic observations with galaxies from cosmological hydrodynamical simulations
• From massive spirals to dwarf irregulars: a new set of tight scaling relations for cold gas and stars driven by disc gravitational instability
• Characterising the Structure of Halo Merger Trees Using a Single Parameter: The Tree Entropy
• xGASS: The connection between angular momentum, mass and atomic gas fraction in nearby galaxies
• WALLABY Pre-Pilot Survey: The effects of angular momentum and environment on the HI gas and star formation properties of galaxies in the Eridanus supergroup
• Angular momentum-related probe of cold gas deficiencies
• Angular momentum evolution of bulge stars in disc galaxies in NIHAO
• Stellar angular momentum distribution linked to galaxy morphology