The effect of ISM turbulence on the gravitational instability of galactic discs

Abstract

We investigate the gravitational instability of galactic discs, treating stars and cold interstellar gas as two distinct components, and taking into account the phenomenology of turbulence in the interstellar medium (ISM), i.e. the Larson-type scaling relations observed in the molecular and atomic gas. Besides deriving general properties of such systems, we analyse a large sample of galaxies from The HI Nearby Galaxy Survey (THINGS), and show in detail how interstellar turbulence affects disc instability in star-forming spirals. We find that turbulence has a significant effect on both the inner and the outer regions of the disc. In particular, it drives the inner gas disc to a regime of transition between two instability phases and makes the outer disc more prone to star-dominated instabilities.

MNRAS, in press. Moderate revision to match the accepted version

References in corpus (13)

• Theory of Star Formation
• The Statistics of Supersonic Isothermal Turbulence
• The Resolved Properties of Extragalactic Giant Molecular Clouds
• Density Fluctuations in MHD Turbulence: Spectra, Intermittency and Topology
• The Fractal Density Structure in Supersonic Isothermal Turbulence: Solenoidal versus Compressive Energy Injection
• Large scale galactic turbulence: can self-gravity drive the observed HI velocity dispersions?
• Is the Scaling of Supersonic Turbulence Universal?
• Scaling Relations of Compressible MHD Turbulence
• Power spectrum of HI intensity fluctuations in DDO 210
• The fractal dimension of star-forming regions at different spatial scales in M33
• HI power spectrum of the spiral galaxy NGC628
• Turbulence measurements from HI absorption spectra
• Probing Turbulence in the Interstellar Medium using Radio-Interferometric Observations of Neutral Hydrogen

Cited by in corpus (15)

• The density structure and star formation rate of non-isothermal polytropic turbulence
• Bar quenching in gas-rich galaxies
• The impact of stellar feedback on the density and velocity structure of the interstellar medium
• Larson's scaling laws, and the gravitational instability of clumpy discs at high redshift
• Characterizing gravitational instability in turbulent multi-component galactic discs
• The SATIN project I: Turbulent multi-phase ISM in Milky Way simulations with SNe feedback from stellar clusters
• Galaxy stellar mass assembly: the difficulty matching observations and semi-analytical predictions
• Spatial Power Spectra of Dust across the Local Group: No Constraint on Disc Scale Height
• Towards a new modelling of gas flows in a semi-analytical model of galaxy formation and evolution
• Spiral arms and disc stability in the Andromeda galaxy
• From giant clumps to clouds IV: extreme star-forming clumps on top of universal cloud scaling relations in gas-rich galaxies
• G.A.S. I: A prescription for turbulence-regulated star formation and its impact on galaxy properties
• Stability of galaxies across morphological sequence
• How does dark matter stabilize disc galaxies?
• Diagnosing Turbulence in the Neutral and Molecular Interstellar Medium of Galaxies