TY - JOUR
T1 - The origin of ultra diffuse galaxies
T2 - Stellar feedback and quenching
AU - Chan, T. K.
AU - Kereš, D.
AU - Wetzel, A.
AU - Hopkins, P. F.
AU - Faucher-Giguère, C. A.
AU - El-Badry, K.
AU - Garrison-Kimmel, S.
AU - Boylan-Kolchin, M.
N1 - Funding Information:
We thank Aaron Romanowsky, Arianna Di Cintio, Timothy Carleton, and Viraj Pandya for helpful discussions. TKC was supported by NSF grant AST-1412153. DK was supported by National Science Foundation grants AST-1412153 and AST-1715101 and the Cottrell Scholar Award from the Research Corporation for Science Advancement. AW was supported by a Caltech-Carnegie Fellowship, in part through the Moore Center for Theoretical Cosmology and Physics at Caltech, and by NASA through grants HST-GO-14734 and HST-AR-15057 from the Space Telescope Science Institute. Support for PFH was provided by an Alfred P. Sloan Research Fellowship, NASA ATP grant NNX14AH35G, and NSF Collaborative Research grant #1411920 and CAREER grant #1455342. CAFG was supported by NSF through grants AST-1412836, AST-1517491, AST-1715216, and CAREER award AST-1652522, and by NASA through grant NNX15AB22G. KE was supported by a Berkeley graduate fellowship, a Hellman award for graduate study, and a National Science Foundation graduate research fellowship. 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. MBK acknowledges support from National Science Foundation grant AST-1517226 and from NASA grants NNX17AG29G and HST-AR-13888, HST-AR-13896, and HST-AR-14282 from the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS5-26555. The simulation presented here used computational resources granted by the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation grant number OCI-1053575, specifically allocation TG-AST120025
Publisher Copyright:
© 2018 The Author(s).
PY - 2018/7/21
Y1 - 2018/7/21
N2 - We test if the cosmological zoom-in simulations of isolated galaxies from the FIRE project reproduce the properties of ultra diffuse galaxies (UDGs). We show that outflows that dynamically heat galactic stars, together with a passively aging stellar population after imposed quenching, naturally reproduce the observed population of red UDGs, without the need for high spin haloes, or dynamical influence from their host cluster. We reproduce the range of surface brightness, radius, and absolute magnitude of the observed red UDGs by quenching simulated galaxies at a range of different times. They represent a mostly uniform population of dark matter-dominated dwarf galaxies with M* ~ 108M⊙, low metallicity, and a broad range of ages; the more massive the UDGs, the older they are. The most massive red UDG in our sample (M* ~ 3 × 108 M⊙) requires quenching at z ~ 3 when its halo reachedMh ~ 1011M⊙. Our simulated UDGs form with normal stellar-to-halo ratios and match the central enclosed masses and the velocity dispersions of the observed UDGs. Enclosed masses remain largely fixed across a broad range of quenching times because the central regions of their dark matter haloes complete their growth early. If our simulated dwarfs are not quenched, they evolve into bluer low surface brightness galaxies with M/L similar to observed field dwarfs. While our simulation sample covers a limited range of formation histories and halo masses, we predict that UDG is a common, and perhaps even dominant, galaxy type around M* ~ 108M⊙, both in the field and in clusters.
AB - We test if the cosmological zoom-in simulations of isolated galaxies from the FIRE project reproduce the properties of ultra diffuse galaxies (UDGs). We show that outflows that dynamically heat galactic stars, together with a passively aging stellar population after imposed quenching, naturally reproduce the observed population of red UDGs, without the need for high spin haloes, or dynamical influence from their host cluster. We reproduce the range of surface brightness, radius, and absolute magnitude of the observed red UDGs by quenching simulated galaxies at a range of different times. They represent a mostly uniform population of dark matter-dominated dwarf galaxies with M* ~ 108M⊙, low metallicity, and a broad range of ages; the more massive the UDGs, the older they are. The most massive red UDG in our sample (M* ~ 3 × 108 M⊙) requires quenching at z ~ 3 when its halo reachedMh ~ 1011M⊙. Our simulated UDGs form with normal stellar-to-halo ratios and match the central enclosed masses and the velocity dispersions of the observed UDGs. Enclosed masses remain largely fixed across a broad range of quenching times because the central regions of their dark matter haloes complete their growth early. If our simulated dwarfs are not quenched, they evolve into bluer low surface brightness galaxies with M/L similar to observed field dwarfs. While our simulation sample covers a limited range of formation histories and halo masses, we predict that UDG is a common, and perhaps even dominant, galaxy type around M* ~ 108M⊙, both in the field and in clusters.
KW - Dark matter
KW - Galaxies: evolution
KW - Galaxies: haloes
KW - Galaxies: kinematics and dynamics
KW - Galaxies: structure
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U2 - 10.1093/MNRAS/STY1153
DO - 10.1093/MNRAS/STY1153
M3 - Article
AN - SCOPUS:85052477473
SN - 0035-8711
VL - 478
SP - 906
EP - 925
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 1
ER -