TY - JOUR
T1 - Hubble Space Telescope Observations of NGC 253 Dwarf Satellites
T2 - Three Ultra-faint Dwarf Galaxies
AU - Mutlu-Pakdil, Burçin
AU - Sand, David J.
AU - Crnojević, Denija
AU - Jones, Michael G.
AU - Caldwell, Nelson
AU - Guhathakurta, Puragra
AU - Seth, Anil C.
AU - Simon, Joshua D.
AU - Spekkens, Kristine
AU - Strader, Jay
AU - Toloba, Elisa
N1 - Funding Information:
B.M.P. is supported by an NSF Astronomy and Astrophysics Postdoctoral Fellowship under award AST-2001663. D.J.S. acknowledges support from NSF grants AST-1821967 and 1813708. Research by D.C. is supported by NSF grant AST-1814208. J.D.S. acknowledges support from NSF grant AST-1412792. J.S. acknowledges support from NSF grant AST-1812856 and the Packard Foundation. K.S. acknowledges support from the Natural Sciences and Engineering Research Council of Canada (NSERC).
Funding Information:
Based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. All the HST data used in this paper can be found in MAST. These observations are associated with program # HST-GO-15938. Support for program # HST-GO-15938 and HST-GO-14259 was provided by NASA through a grant from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. The Parkes telescope is part of the Australia Telescope which is funded by the Commonwealth of Australia for operation as a National Facility managed by CSIRO.
Publisher Copyright:
© 2022. The Author(s). Published by the American Astronomical Society.
PY - 2022/2/1
Y1 - 2022/2/1
N2 - We present deep Hubble Space Telescope (HST) imaging of five faint dwarf galaxies associated with the nearby spiral NGC 253 (D ≈ 3.5 Mpc). Three of these are newly discovered dwarf galaxies, while all five were found in the Panoramic Imaging Survey of Centaurus and Sculptor, a Magellan+Megacam survey to identify faint dwarfs and other substructures in resolved stellar light around massive galaxies outside of the Local Group. Our HST data reach ≲3 magnitudes below the tip of the red giant branch for each dwarf, allowing us to derive their distances, structural parameters, and luminosities. All five systems contain mostly old, metal-poor stellar populations (age ∼ 12 Gyr, [M/H] ≳ -1.5) and have sizes (r h ∼110-3000 pc) and luminosities (M V ∼-7 to -12 mag) largely consistent with Local Group dwarfs. The three new NGC 253 satellites are among the faintest systems discovered beyond the Local Group. We also use archival H i data to place limits on the gas content of our discoveries. Deep imaging surveys such as our program around NGC 253 promise to elucidate the faint end of the satellite luminosity function and its scatter across a range of galaxy masses, morphologies, and environments in the decade to come.
AB - We present deep Hubble Space Telescope (HST) imaging of five faint dwarf galaxies associated with the nearby spiral NGC 253 (D ≈ 3.5 Mpc). Three of these are newly discovered dwarf galaxies, while all five were found in the Panoramic Imaging Survey of Centaurus and Sculptor, a Magellan+Megacam survey to identify faint dwarfs and other substructures in resolved stellar light around massive galaxies outside of the Local Group. Our HST data reach ≲3 magnitudes below the tip of the red giant branch for each dwarf, allowing us to derive their distances, structural parameters, and luminosities. All five systems contain mostly old, metal-poor stellar populations (age ∼ 12 Gyr, [M/H] ≳ -1.5) and have sizes (r h ∼110-3000 pc) and luminosities (M V ∼-7 to -12 mag) largely consistent with Local Group dwarfs. The three new NGC 253 satellites are among the faintest systems discovered beyond the Local Group. We also use archival H i data to place limits on the gas content of our discoveries. Deep imaging surveys such as our program around NGC 253 promise to elucidate the faint end of the satellite luminosity function and its scatter across a range of galaxy masses, morphologies, and environments in the decade to come.
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U2 - 10.3847/1538-4357/ac4418
DO - 10.3847/1538-4357/ac4418
M3 - Article
AN - SCOPUS:85125857051
VL - 926
JO - Astrophysical Journal
JF - Astrophysical Journal
SN - 0004-637X
IS - 1
M1 - 77
ER -