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Title: Star formation histories of dwarf galaxies in the FIRE simulations: dependence on mass and Local Group environment
ABSTRACT We study star formation histories (SFHs) of 500 dwarf galaxies (stellar mass $M_\ast =10^5\!-\!10^9\, \rm {M}_\odot$) from FIRE-2 cosmological zoom-in simulations. We compare dwarfs around individual Milky Way (MW)-mass galaxies, dwarfs in Local Group (LG)-like environments, and true field (i.e. isolated) dwarf galaxies. We reproduce observed trends wherein higher mass dwarfs quench later (if at all), regardless of environment. We also identify differences between the environments, both in terms of ‘satellite versus central’ and ‘LG versus individual MW versus isolated dwarf central.’ Around the individual MW-mass hosts, we recover the result expected from environmental quenching: central galaxies in the ‘near field’ have more extended SFHs than their satellite counterparts, with the former more closely resemble isolated (true field) dwarfs (though near-field centrals are still somewhat earlier forming). However, this difference is muted in the LG-like environments, where both near-field centrals and satellites have similar SFHs, which resemble satellites of single MW-mass hosts. This distinction is strongest for M* = 106–$10^7\, \rm {M}_\odot$ but exists at other masses. Our results suggest that the paired halo nature of the LG may regulate star formation in dwarf galaxies even beyond the virial radii of the MW and Andromeda. Caution is needed when comparing more » zoom-in simulations targeting isolated dwarf galaxies against observed dwarf galaxies in the LG. « less
Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ; ;
Award ID(s):
1752913 1715216 1715101 1715847
Publication Date:
NSF-PAR ID:
10174835
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
489
Issue:
4
Page Range or eLocation-ID:
4574 to 4588
ISSN:
0035-8711
Sponsoring Org:
National Science Foundation
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