Abstract
We present a suite of high-resolution simulations of an isolated dwarf galaxy using four different hydrodynamical codes: Gizmo, Arepo, Gadget, and Ramses. All codes adopt the same physical model, which includes radiative cooling, photoelectric heating, star formation, and supernova (SN) feedback. Individual SN explosions are directly resolved without resorting to subgrid models, eliminating one of the major uncertainties in cosmological simulations. We find reasonable agreement on the time-averaged star formation rates as well as the joint density-temperature distributions between all codes. However, the Lagrangian codes show significantly burstier star formation, larger SN-driven bubbles, and stronger galactic outflows compared to the Eulerian code. This is caused by the behavior in the dense, collapsing gas clouds when the Jeans length becomes unresolved: Gas in Lagrangian codes collapses to much higher densities than that in Eulerian codes, as the latter is stabilized by the minimal cell size. Therefore, more of the gas cloud is converted to stars and SNe are much more clustered in the Lagrangian models, amplifying their dynamical impact. The differences between Lagrangian and Eulerian codes can be reduced by adopting a higher star formation efficiency in Eulerian codes, which significantly enhances SN clustering in the latter. Adopting a zero SN delay time reduces burstiness in all codes, resulting in vanishing outflows as SN clustering is suppressed.
| Original language | English (US) |
|---|---|
| Article number | 132 |
| Journal | Astrophysical Journal |
| Volume | 950 |
| Issue number | 2 |
| DOIs | |
| State | Published - Jun 1 2023 |
Funding
We thank the anonymous referee for the constructive comments that helped improve the manuscript, in particular for suggesting the additional run in Appendix . We thank Volker Springel and Chang-Goo Kim for a stimulating discussion. C.Y.H. acknowledges support from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) via German-Israel Project Cooperation grant STE1869/2-1 GE625/17-1 and NASA ATP grant 80NSSC22K0716. The work of MCS was supported by a grant from the Simons Foundation (CCA 668771, LEH) and by the DFG under Germany\u2019s Excellence Strategy EXC 2181/1-390900948 (the Heidelberg STRUCTURES Excellence Cluster). The Center for Computational Astrophysics is supported by the Simons Foundation. G.L.B. acknowledges support from the NSF (AST-2108470, XSEDE), a NASA TCAN award, and the Simons Foundation through their support of the Learning the Universe Collaboration. B.B. thanks the Alfred P. Sloan Foundation and the Packard Foundation for support as well as the support of NASA grant No. 80NSSC20K0500. Y.L. acknowledges financial support from NSF grant AST- 2107735 and NASA grant 80NSSC22K0668.
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science