Oscar Agertz
Associate Professor / Senior university lecturer / Wallenberg Academy Fellow
The impact of stellar feedback on the density and velocity structure of the interstellar medium
Author
Summary, in English
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 observedHI in local spiral galaxies from THINGS (TheHI Nearby Galaxy Survey). Our models with stellar feedback give an excellent match to the observed THINGS HI 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 HI 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.
Department/s
- Lund Observatory - Has been reorganised
Publishing year
2017
Language
English
Pages
1093-1110
Publication/Series
Monthly Notices of the Royal Astronomical Society
Volume
466
Issue
1
Document type
Journal article
Publisher
Oxford University Press
Topic
- Astronomy, Astrophysics and Cosmology
Keywords
- Galaxies: evolution
- Galaxies: ISM
- Galaxies: spiral
- Galaxies: structure
Status
Published
ISBN/ISSN/Other
- ISSN: 0035-8711