4.7 Article

Role of cosmic-ray streaming and turbulent damping in driving galactic winds

Journal

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Volume 490, Issue 1, Pages 1271-1282

Publisher

OXFORD UNIV PRESS
DOI: 10.1093/mnras/stz2568

Keywords

cosmic rays; galaxies: evolution; galaxies: star formation

Funding

  1. Rackham Merit Fellowship at the University of Michigan
  2. NASA ATP [NNX17AK70G, 12-ATP12-0017]
  3. NSF AST grant [1816234]
  4. NASA TCAN [144AAG1967]
  5. NSF [AST 1713722, AST 1715140]

Ask authors/readers for more resources

Large-scale galactic winds driven by stellar feedback are one phenomenon that influences the dynamical and chemical evolution of a galaxy, redistributing material throughout the circumgalatic medium. Non-thermal feedback from galactic cosmic rays (CRs) - high-energy charged particles accelerated in supernovae and young stars - can impact the efficiency of wind driving. The streaming instability limits the speed at which they can escape. However, in the presence of turbulence, the streaming instability is subject to suppression that depends on the magnetization of turbulence given by its Alfven Mach number. While previous simulations that relied on a simplified model of CR transport have shown that super-Alfvenic streaming of CRs enhances galactic winds, in this paper we take into account a realistic model of streaming suppression. We perform three-dimensional magnetohydrodynamic simulations of a section of a galactic disc and find that turbulent damping dependent on local magnetization of turbulent interstellar medium (ISM) leads to more spatially extended gas and CR distributions compared to the earlier streaming calculations, and that scale heights of these distributions increase for stronger turbulence. Our results indicate that the star formation rate increases with the level of turbulence in the ISM. We also find that the instantaneous wind mass loading is sensitive to local streaming physics with the mass loading dropping significantly as the strength of turbulence increases.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.7
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available