A Caltech Library Service

Stellar feedback in galaxies and the origin of galaxy-scale winds

Hopkins, Philip F. and Quataert, Eliot and Murray, Norman (2012) Stellar feedback in galaxies and the origin of galaxy-scale winds. Monthly Notices of the Royal Astronomical Society, 421 (4). pp. 3522-3537. ISSN 0035-8711.

[img] PDF - Published Version
See Usage Policy.

[img] PDF - Accepted Version
See Usage Policy.


Use this Persistent URL to link to this item:


Feedback from massive stars is believed to play a critical role in driving galactic super‐winds that enrich the intergalactic medium and shape the galaxy mass function, mass–metallicity relation and other global galaxy properties. In previous papers, we have introduced new numerical methods for implementing stellar feedback on sub‐giant molecular cloud (sub‐GMC) through galactic scales in numerical simulations of galaxies; the key physical processes include radiation pressure in the ultraviolet through infrared, supernovae (Type I and Type II), stellar winds (‘fast’ O star through ‘slow’ asymptotic giant branch winds), and H II photoionization. Here, we show that these feedback mechanisms drive galactic winds with outflow rates as high as ∼10–20 times the galaxy star formation rate. The mass‐loading efficiency (wind mass‐loss rate divided by the star formation rate) scales roughly as Ṁ_(wind)/Ṁ★ ∝ V_c⁻¹ (where V_c is the galaxy circular velocity), consistent with simple momentum‐conservation expectations. We use our suite of simulations to study the relative contribution of each feedback mechanism to the generation of galactic winds in a range of galaxy models, from Small Magellanic Cloud like dwarfs and Milky Way (MW) analogues to z∼ 2 clumpy discs. In massive, gas‐rich systems (local starbursts and high‐z galaxies), radiation pressure dominates the wind generation. By contrast, for MW‐like spirals and dwarf galaxies the gas densities are much lower and sources of shock‐heated gas such as supernovae and stellar winds dominate the production of large‐scale outflows. In all of our models, however, the winds have a complex multiphase structure that depends on the interaction between multiple feedback mechanisms operating on different spatial scales and time‐scales: any single feedback mechanism fails to reproduce the winds observed. We use our simulations to provide fitting functions to the wind mass loading and velocities as a function of galaxy properties, for use in cosmological simulations and semi‐analytic models. These differ from typically adopted formulae with an explicit dependence on the gas surface density that can be very important in both low‐density dwarf galaxies and high‐density gas‐rich galaxies.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Hopkins, Philip F.0000-0003-3729-1684
Quataert, Eliot0000-0001-9185-5044
Additional Information:© 2012 The Author. Monthly Notices of the Royal Astronomical Society © 2012 RAS. Accepted 2012 January 18. Received 2012 January 16; in original form 2011 October 17. We thank Todd Thompson and Romeel Davé for helpful discussions. Support for PFH was provided by the Miller Institute for Basic Research in Science, University of California Berkeley. EQ is supported in part by NASA grant NNG06GI68G and the David and Lucile Packard Foundation. NM is supported in part by NSERC and by the Canada Research Chairs programme.
Funding AgencyGrant Number
Miller Institute for Basic Research in ScienceUNSPECIFIED
David and Lucile Packard FoundationUNSPECIFIED
Natural Sciences and Engineering Research Council of Canada (NSERC)UNSPECIFIED
Canada Research Chairs ProgramUNSPECIFIED
Subject Keywords:stars: formation, galaxies: active, galaxies: evolution, galaxies: formation, cosmology: theory
Issue or Number:4
Record Number:CaltechAUTHORS:20200601-143025126
Persistent URL:
Official Citation:Philip F. Hopkins, Eliot Quataert, Norman Murray, Stellar feedback in galaxies and the origin of galaxy‐scale winds, Monthly Notices of the Royal Astronomical Society, Volume 421, Issue 4, April 2012, Pages 3522–3537,
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:103618
Deposited By: George Porter
Deposited On:01 Jun 2020 22:04
Last Modified:01 Jun 2020 22:04

Repository Staff Only: item control page