Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published November 2019 | Submitted + Published
Journal Article Open

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∗=10⁵−10⁹ M_⊙⁠) 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* = 10⁶–10⁷M⊙ 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 zoom-in simulations targeting isolated dwarf galaxies against observed dwarf galaxies in the LG.

Additional Information

© 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model). Accepted 2019 September 4. Received 2019 July 19; in original form 2019 March 26. Published: 10 September 2019. The authors thank Cameron Hummels, Peter Behroozi, Stephanie Tonnesen, and Zach Hafen for valuable discussions, Dan Weisz and Evan Skillman for making publicly available the observed SFHs, and Oliver Hahn and Peter Behroozi for making MUSIC and Rockstar public, respectively. This work was performed in part at the Aspen Center for Physics, which is supported by National Science Foundation grant PHY-1607611. Support for SGK was provided by NASA through Einstein Postdoctoral Fellowship grant number PF5-160136 awarded by the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for NASA under contract NAS8-03060. SGK, AW, JSB, KEB, RES, MBK, and CAFG were supported by NASA through ATP #80NSSC18K0562, 80NSSC18K1097, HST-GO-12914, HST-GO-14734, HST-GO-14191, HST-AR-13888, HST-AR-13896, HST-AR-13921, HST-AR-14282, HST-AR-14554, HST-AR-15006, HST-AR-15057, JPL 1589742, NNX17AG29G, NNX15AB22G, and 17-ATP17-0067, many of which are awarded by STScI, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under NASA contract NAS5-26555. SGK, PFH, JSB, AG, KEB, MBK, AF, TKC, DK, and CAFG were supported by the NSF through CAREER grant #1455342, CAREER grant AST-1752913, CAREER grant AST-1652522, Collaborative Research grant #1715847, AST-1517226, AST-1517491, AST-1518291, AST-1715101, AST-1715216, and an NSF Graduate Research Fellowship. Additional support was provided by the Moore Center for Theoretical Cosmology and Physics at Caltech, the Alfred P. Sloan Research Fellowship, a Berkeley graduate fellowship, a Hellman award for graduate study, the Lee A. DuBridge Postdoctoral Scholarship in Astrophysics, the Swiss National Science Foundation (grant #157591), and the Cottrell Scholarship Award from the Research Corporation for Science Advancement. The Flatiron Institute is supported by the Simons Foundation. Numerical calculations were run on the Caltech compute cluster 'Wheeler,' allocations from XSEDE TG-AST130039 and PRAC NSF.1713353 supported by the NSF, NASA HEC SMD-16-7223, and SMD-16-7592, and High Performance Computing at Los Alamos National Labs. This work also made use of Astropy, a community-developed core PYTHON package for Astronomy (Astropy Collaboration et al. 2013; The Astropy Collaboration et al. 2018), matplotlib (Hunter 2007), numpy (van der Walt, Colbert & Varoquaux 2011), scipy (Jones et al. 2001), ipython (Perez & Granger 2007), yt (Turk et al. 2011), ytree (Smith & Lang 2018), and NASA's Astrophysics Data System.

Attached Files

Published - stz2507.pdf

Submitted - 1903.10515.pdf

Files

1903.10515.pdf
Files (21.5 MB)
Name Size Download all
md5:40ccc8cb1c21e26d2fa1f83a9db59b52
3.5 MB Preview Download
md5:e1bb82f42bf8f5cd88a54794583fa03e
18.1 MB Preview Download

Additional details

Created:
August 19, 2023
Modified:
October 18, 2023