How runaway stars boost galactic outflows
arXiv:2003.12297 · doi:10.1093/mnras/staa889
Abstract
Roughly ten per cent of OB stars are kicked out of their natal clusters before ending their life as supernovae. These so-called runaway stars can travel hundreds of parsecs into the low-density interstellar medium, where momentum and energy from stellar feedback is efficiently deposited. In this work we explore how this mechanism affects large scale properties of the galaxy, such as outflows. To do so we use a new model which treats OB stars and their associated feedback processes on a star-by-star basis. With this model we compare two hydrodynamical simulations of Milky Way-like galaxies, one where we include runaways, and one where we ignore them. Including runaway stars leads to twice as many supernovae explosions in regions with gas densities ranging from 1e-5 cm^-3 to 1e-3 cm^-3. This results in more efficient heating of the inter-arm regions, and drives strong galactic winds with mass loading factors boosted by up to one order of magnitude. These outflows produce a more massive and extended multi-phase circumgalactic medium, as well as a population of dense clouds in the halo. Conversely, since less energy and momentum is released in the dense star forming regions, the cold phase of the interstellar medium is less disturbed by feedback effects.
14 pages, 10 figures, accepted for publication in MNRAS, minor changes to text
References in corpus (30)
- Star Formation and Feedback in Smoothed Particle Hydrodynamic Simulations--I. Isolated Galaxies
- Slow Star Formation in Dense Gas: Evidence and Implications
- Compaction and Quenching of High-z Galaxies in Cosmological Simulations: Blue and Red Nuggets
- The COS-Halos Survey: Physical Conditions and Baryonic Mass in the Low-Redshift Circumgalactic Medium
- Momentum Injection by Supernovae in the Interstellar Medium
- What is Driving the HI Velocity Dispersion?
- The empirical metallicity dependence of the mass-loss rate of O- and early B-type stars
- The role of stellar feedback in the formation of galaxies
- Turbulent Structure of a Stratified Supernova-Driven Interstellar Medium
- On the interplay between star formation and feedback in galaxy formation simulations
- A Superbubble Feedback Model for Galaxy Simulations
- How cold is cold dark matter? Small scales constraints from the flux power spectrum of the high-redshift Lyman-alpha forest
- Distances to Galactic high-velocity clouds. I. Cohen Stream, complex GCP, cloud g1
- A simple multigrid scheme for solving the Poisson equation with arbitrary domain boundaries
- Observational Evidence of Dynamic Star Formation Rate in Milky Way Giant Molecular Clouds
- Mutual influence of supernovae and molecular clouds
- A Review of Recent Observations of Galactic Winds Driven by Star Formation
- Simulations of the star-forming molecular gas in an interacting M51-like galaxy
- Snap, Crackle, Pop: sub-grid supernova feedback in AMR simulations of disk galaxies
- On the origin of field O-type stars
- The formation of low metallicity globular clusters in dwarf galaxy mergers
- The effect of stellar winds on the formation of a protocluster
- The impact of stellar feedback on the density and velocity structure of the interstellar medium
- Discreteness Effects in Lambda Cold Dark Matter Simulations: A Wavelet-Statistical View
- A simple method to convert sink particles into stars
- Characterizing gravitational instability in turbulent multi-component galactic discs
- Simple Yet Powerful: Hot Galactic Outflows Driven by Supernovae
- On the Observed Diversity of Star Formation Efficiencies in Giant Molecular Clouds
- Supernovae feedback propagation: the role of turbulence
- Tracing dense and diffuse neutral hydrogen in the halo of the Milky Way