Discovery of two neighboring satellites in the Carina constellation with MagLiteS

• Verfasst von: Torrealba, Gabriel [VerfasserIn]
• Verfasst von: Martin, Nicolas F. [VerfasserIn]
• Verfasst von: Martínez-Delgado, David [VerfasserIn]
• Verfasst von: Noël, Noelia E. D. [VerfasserIn]
• Titel: Discovery of two neighboring satellites in the Carina constellation with MagLiteS
• Verf.angabe: G. Torrealba, V. Belokurov, S.E. Koposov, K. Bechtol, A. Drlica-Wagner, K.A.G. Olsen, A.K. Vivas, B. Yanny, P. Jethwa, A.R. Walker, T.S. Li, S. Allam, B.C. Conn, C. Gallart, R.A. Gruendl, D.J. James, M.D. Johnson, K. Kuehn, N. Kuropatkin, N.F. Martin, D. Martinez-Delgado, D.L. Nidever, N.E.D. Noël, J.D. Simon, G.S. Stringfellow, D.L. Tucker
• E-Jahr: 2018
• Jahr: 22 Jan 2018
• Umfang: 14 S.
• Fussnoten: Gesehen am 14.03.2018
• Titel Quelle: Enthalten in: De.arxiv.org
• Ort Quelle: [S.l.] : Arxiv.org, 1991
• Jahr Quelle: 2018
• Band/Heft Quelle: (2018) Artikel-Nummer 1801.07279, 14 Seiten
• DOI: doi:10.48550/arXiv.1801.07279
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Astrophysics - Astrophysics of Galaxies
• K10plus-PPN: 1571041273

Abstract

We report the discovery of two ultra-faint satellites in the vicinity of the Large Magellanic Cloud (LMC) in data from the Magellanic Satellites Survey (MagLiteS). Situated 18$^{\circ}$ ($\sim 20$ kpc) from the LMC and separated from each other by only $18^\prime$, Carina~II and III form an intriguing pair. By simultaneously modeling the spatial and the color-magnitude stellar distributions, we find that both Carina~II and Carina~III are likely dwarf galaxies, although this is less clear for Carina~III. There are in fact several obvious differences between the two satellites. While both are well described by an old and metal poor population, Carina~II is located at $\sim 36$ kpc from the Sun, with $M_V\sim-4.5$ and $r_h\sim 90$ pc, and it is further confirmed by the discovery of 3 RR Lyrae at the right distance. In contrast, Carina~III is much more elongated, measured to be fainter ($M_V\sim-2.4$), significantly more compact ($r_h\sim30$ pc), and closer to the Sun, at $\sim 28$ kpc, placing it only 8 kpc away from Car~II. Together with several other systems detected by the Dark Energy Camera, Carina~II and III form a strongly anisotropic cloud of satellites in the vicinity of the Magellanic Clouds.