4.7 Article

EDGE: a new approach to suppressing numerical diffusion in adaptive mesh simulations of galaxy formation

Journal

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Volume 501, Issue 2, Pages 1755-1765

Publisher

OXFORD UNIV PRESS
DOI: 10.1093/mnras/staa3645

Keywords

methods: numerical; galaxies: dwarf; cosmology: miscellaneous

Funding

  1. EU Framework Programme for Research and Innovation H2020 [818085 GMGalaxies]
  2. Royal Society
  3. Knut and AliceWallenberg Foundation
  4. Royal Physiographic Society in Lund
  5. Swedish Research Council [2014-5791]
  6. UCL Cosmoparticle Initiative

Ask authors/readers for more resources

A new method is introduced to reduce numerical diffusion in adaptive mesh refinement (AMR) simulations of cosmological galaxy formation, with particular focus on dwarf galaxies. By using genetic modification to create 'velocity-zeroed' initial conditions, it suppresses grid-relative streaming without significantly altering large-scale structure or dark matter accretion history. The resulting simulation shows a more physical onset of star formation, especially recommended for small galaxies at high redshifts.
We introduce a new method to mitigate numerical diffusion in adaptive mesh refinement (AMR) simulations of cosmological galaxy formation, and study its impact on a simulated dwarf galaxy as part of the 'EDGE' project. The target galaxy has a maximum circular velocity of 21 km s(-1) but evolves in a region that is moving at up to 90 km s(-1) relative to the hydrodynamic grid. In the absence of any mitigation, diffusion softens the filaments feeding our galaxy. As a result, gas is unphysically held in the circumgalactic medium around the galaxy for 320 Myr, delaying the onset of star formation until cooling and collapse eventually triggers an initial starburst at z = 9. Using genetic modification, we produce 'velocity-zeroed' initial conditions in which the grid-relative streaming is strongly suppressed; by design, the change does not significantly modify the large-scale structure or dark matter accretion history. The resulting simulation recovers a more physical, gradual onset of star formation starting at z = 17. While the final stellar masses are nearly consistent (4.8 x 10(6) M-circle dot and 4.4 x 10(6) M-circle dot for unmodified and velocity-zeroed, respectively), the dynamical and morphological structure of the z = 0 dwarf galaxies are markedly different due to the contrasting histories. Our approach to diffusion suppression is suitable for any AMR zoom cosmological galaxy formation simulations, and is especially recommended for those of small galaxies at high redshift.

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