A stochastic model to reproduce the star formation history of individual galaxies in hydrodynamic simulations

Wang, Yang; Napolitano, Nicola R.; Cui, Weiguang; Li, Xiao Dong; Knebe, Alexander; Power, Chris; Pearce, Frazer; Tang, Lin; Yepes, Gustavo; Kang, Xi

Abstract

The star formation history (SFH) of galaxies is critical for understanding galaxy evolution. Hydrodynamical simulations enable us to precisely reconstruct the SFH of galaxies and establish a link to the underlying physical processes. In this work, we present a model to describe individual galaxies' SFHs from three simulations: TheThreeHundred, Illustris-1, and TNG100-1. This model divides the galaxy SFH into two distinct components: the 'main sequence' and the 'variation'. The 'main sequence' part is generated by tracing the history of the SFR - M∗ main sequence of galaxies across time. The 'variation' part consists of the scatter around the main sequence, which is reproduced by fractional Brownian motions. We find that: (1) the evolution of the main sequence varies between simulations; (2) fractional Brownian motions can reproduce many features of SFHs; however, discrepancies still exist; and (3) the variations and mass-loss rate are crucial for reconstructing the SFHs of the simulations. This model provides a fair description of the SFHs in simulations. On the other hand, by correlating the fractional Brownian motion model to simulation data, we provide a 'standard' against which to compare simulations.

Citation

Wang, Y., Napolitano, N. R., Cui, W., Li, X. D., Knebe, A., Power, C., …Kang, X. (2022). A stochastic model to reproduce the star formation history of individual galaxies in hydrodynamic simulations. Monthly Notices of the Royal Astronomical Society, 515(3), 3249-3269. https://doi.org/10.1093/mnras/stac1956

• Journal Article Type: Article
• Acceptance Date: Jul 7, 2022
• Online Publication Date: Jul 13, 2022
• Publication Date: Sep 1, 2022
• Deposit Date: Dec 20, 2022
• Publicly Available Date: Dec 21, 2022
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 515
• Issue: 3
• Pages: 3249-3269
• DOI: https://doi.org/10.1093/mnras/stac1956
• Keywords: Space and Planetary Science, Astronomy and Astrophysics
• Public URL: https://nottingham-repository.worktribe.com/output/10357767
• Publisher URL: https://academic.oup.com/mnras/article/515/3/3249/6643333