The impact of stellar feedback on the density and velocity structure of the interstellar medium
Journal article, 2017

We study the impact of stellar feedback in shaping the density and velocity structure of neutral hydrogen (H I) in disc galaxies. For our analysis, we carry out ∼4.6 pc resolution N-body+adaptive mesh refinement hydrodynamic simulations of isolated galaxies, set up to mimic a Milky Way and a Large and Small Magellanic Cloud. We quantify the density and velocity structure of the interstellar medium using power spectra and compare the simulated galaxies to observed H I in local spiral galaxies from THINGS (The H I Nearby Galaxy Survey). Our models with stellar feedback give an excellent match to the observed THINGS H I density power spectra. We find that kinetic energy power spectra in feedback-regulated galaxies, regardless of galaxy mass and size, show scalings in excellent agreement with supersonic turbulence (E(k) ∝ k−2) on scales below the thickness of the H I layer. We show that feedback influences the gas density field, and drives gas turbulence, up to large (kpc) scales. This is in stark contrast to density fields generated by large-scale gravity-only driven turbulence. We conclude that the neutral gas content of galaxies carries signatures of stellar feedback on all scales.

Author

Kearn Grisdale

University of Surrey

Oscar Agertz

University of Surrey

Lund University

Alessandro Romeo

Chalmers, Earth and Space Sciences, Radio Astronomy and Astrophysics

Florent Renaud

University of Surrey

Justin I. Read

University of Surrey

Monthly Notices of the Royal Astronomical Society

0035-8711 (ISSN) 1365-2966 (eISSN)

Vol. 466 1 1093-1110

Subject Categories

Astronomy, Astrophysics and Cosmology

Roots

Basic sciences

DOI

10.1093/mnras/stw3133

More information

Latest update

3/2/2018 9