Hydrodynamical simulations of galaxy formation with non-Gaussian initial conditions
- Author(s)
- Clément Stahl, Yohan Dubois, Benoit Famaey, Oliver Hahn, Rodrigo Ibata, Katarina Kraljic, Thomas Montandon
- Abstract
Collisionless simulations of structure formation with significant local primordial non-Gaussianities at Mpc scales have shown that a non-Gaussian tail favouring underdensities, with a negative f
NL parameter, can significantly change the merging history of galaxy-sized dark matter halos, which then typically assemble later than in vanilla ΛCDM. Moreover, such a small-scale negative f
NL could have interesting consequences for the cosmological S
8 tension. Here, we complement our previous work on collisionless simulations with new hydrodynamical simulations of galaxy formation in boxes of 30 Mpc/h, using the RAMSES code. In particular, we show that all feedback prescriptions being otherwise identical, simulations with a negative f
NL ∼ -1000 on small scales, hence forming galaxies a bit later than in vanilla ΛCDM, allow to form simulated galaxies with more disky kinematics than in the vanilla case. Therefore, such small-scale primordial non-Gaussianities could potentially help alleviate, simultaneously, tensions in cosmology and galaxy formation. These hydrodynamical simulations on small scales will need to be complemented with larger box simulations with scale-dependent non-Gaussianities, to statistically confirm these trends and explore their observational consequences in further detail.
- Organisation(s)
- Department of Astrophysics
- External organisation(s)
- Université de Strasbourg, Sorbonne Université
- Journal
- Journal of Cosmology and Astroparticle Physics (JCAP)
- Volume
- 2023
- No. of pages
- 14
- ISSN
- 1475-7516
- DOI
- https://doi.org/10.1088/1475-7516/2023/09/036
- Publication date
- 09-2023
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103004 Astrophysics, 103044 Cosmology, 103043 Computational physics
- Keywords
- ASJC Scopus subject areas
- Astronomy and Astrophysics
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/93953ce4-8e45-4875-af8c-091f70cd85ac