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Title: DELVE-DEEP Survey: The Faint Satellite System of NGC 55
Abstract We report the first comprehensive census of the satellite dwarf galaxies around NGC 55 (2.1 Mpc) as a part of the DECam Local Volume Exploration DEEP (DELVE-DEEP) survey. NGC 55 is one of four isolated, Magellanic analogs in the Local Volume around which DELVE-DEEP aims to identify faint dwarfs and other substructures. We employ two complementary detection methods: one targets fully resolved dwarf galaxies by identifying them as stellar overdensities, while the other focuses on semiresolved dwarf galaxies, detecting them through shredded unresolved light components. As shown through extensive tests with injected galaxies, our search is sensitive to candidates down toMV ≲ −6.6 and surface brightnessμ ≲ 28.5 mag arcsec2, and ∼80% complete down toMV ≲ −7.8. We do not report any new confirmed satellites beyond two previously known systems, ESO 294–010 and NGC 55-dw1. We construct the satellite luminosity function of NGC 55 and find it to be consistent with the predictions from cosmological simulations. As one of the first complete luminosity functions for a Magellanic analog, our results provide a glimpse of the constraints on low-mass-host satellite populations that will be further explored by upcoming surveys, such as the Vera C. Rubin Observatory’s Legacy Survey of Space and Time.  more » « less
Award ID(s):
2307126 2108168 2407526 2205863
PAR ID:
10636828
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; « less
Publisher / Repository:
AAS Journals
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
990
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
108
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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