Sand, D. J.
Simon, J. D.
AffiliationUniv Arizona, Steward Observ
Univ Arizona, Dept Astron
galaxies: groups: individual (Cen A)
galaxies: luminosity function, mass function
MetadataShow full item record
PublisherIOP PUBLISHING LTD
CitationD. Crnojević et al 2019 ApJ 872 80
Rights© 2019. The American Astronomical Society. All rights reserved.
Collection InformationThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at firstname.lastname@example.org.
AbstractThe Panoramic Imaging Survey of Centaurus and Sculptor (PISCeS) is constructing a wide-field map of the resolved stellar populations in the extended halos of these two nearby, prominent galaxies. We present new Magellan/Megacam imaging of a similar to 3 deg(2) area around Centaurus A (Cen A), which filled in much of our coverage to its south, leaving a nearly complete halo map out to a projected radius of similar to 150 kpc and allowing us to identify two new resolved dwarf galaxies. We have additionally obtained deep Hubble Space Telescope (HST) optical imaging of 11 out of the 13 candidate dwarf galaxies identified around Cen A and presented in Crnojevic et al. 2016a: seven are confirmed to be satellites of Cen A, while four are found to be background galaxies. We derive accurate distances, structural parameters, luminosities, and photometric metallicities for the seven candidates confirmed by our HST/ACS imaging. We further study the stellar population along the similar to 60 kpc long (in projection) stream associated with Dw3, which likely had an initial brightness of M-V similar to -15 and shows evidence for a metallicity gradient along its length. Using the total sample of 11 dwarf satellites discovered by the PISCeS survey, as well as 13 brighter previously known satellites of Cen A, we present a revised galaxy luminosity function for the Cen A group down to a limiting magnitude of M-V similar to -8, which has a slope of -1.14 +/- 0.17, comparable to that seen in the Local Group and in other nearby groups of galaxies.
VersionFinal published version
SponsorsNASA from the Space Telescope Science Institute [NNX14AF84G, HST-GO-13856.001]; NSF [AST-1514763, AST-1814208, AST-1821967, AST-1821987, AST-1813708, AST-1813466, AST-1010039, AST-1412504, AST-1412792]; Packard Fellowship; Natural Sciences and Engineering Research Council of Canada (NSERC); National Science Foundation [PHYS-1066293]; Aspen Center for Physics; Smithsonian Astrophysical Observatory; NASA [NNX14AF84G, NAS 5-26555]
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