TY - JOUR
T1 - HYDRA II
T2 - A FAINT AND COMPACT MILKY WAY DWARF GALAXY FOUND IN THE SURVEY OF THE MAGELLANIC STELLAR HISTORY
AU - Martin, Nicolas F.
AU - Nidever, David L.
AU - Besla, Gurtina
AU - Olsen, Knut
AU - Walker, Alistair R.
AU - Vivas, A. Katherina
AU - Gruendl, Robert A.
AU - Kaleida, Catherine C.
AU - Muñoz, Ricardo R.
AU - Blum, Robert D.
AU - Saha, Abhijit
AU - Conn, Blair C.
AU - Bell, Eric F.
AU - Chu, You Hua
AU - Cioni, Maria Rosa L.
AU - De Boer, Thomas J.L.
AU - Gallart, Carme
AU - Jin, Shoko
AU - Kunder, Andrea
AU - Majewski, Steven R.
AU - Martinez-Delgado, David
AU - Monachesi, Antonela
AU - Monelli, Matteo
AU - Monteagudo, Lara
AU - Noël, Noelia E.D.
AU - Olszewski, Edward W.
AU - Stringfellow, Guy S.
AU - Van Der Marel, Roeland P.
AU - Zaritsky, Dennis
N1 - Publisher Copyright:
© 2015. The American Astronomical Society. All rights reserved.
PY - 2015/5/1
Y1 - 2015/5/1
N2 - We present the discovery of a new dwarf galaxy, Hydra II, found serendipitously within the data from the ongoing Survey of the Magellanic Stellar History conducted with the Dark Energy Camera on the Blanco 4 m Telescope. The new satellite is compact (rh = 68 ± 11 pc) and faint (MV = -4.8 ± 0.3), but well within the realm of dwarf galaxies. The stellar distribution of Hydra II in the color-magnitude diagram is well-described by a metal-poor ([Fe/H] = -2.2) and old (13 Gyr) isochrone and shows a distinct blue horizontal branch, some possible red clump stars, and faint stars that are suggestive of blue stragglers. At a heliocentric distance of 134 ± 10 kpc, Hydra II is located in a region of the Galactic halo that models have suggested may host material from the leading arm of the Magellanic Stream. A comparison with N-body simulations hints that the new dwarf galaxy could be or could have been a satellite of the Magellanic Clouds.
AB - We present the discovery of a new dwarf galaxy, Hydra II, found serendipitously within the data from the ongoing Survey of the Magellanic Stellar History conducted with the Dark Energy Camera on the Blanco 4 m Telescope. The new satellite is compact (rh = 68 ± 11 pc) and faint (MV = -4.8 ± 0.3), but well within the realm of dwarf galaxies. The stellar distribution of Hydra II in the color-magnitude diagram is well-described by a metal-poor ([Fe/H] = -2.2) and old (13 Gyr) isochrone and shows a distinct blue horizontal branch, some possible red clump stars, and faint stars that are suggestive of blue stragglers. At a heliocentric distance of 134 ± 10 kpc, Hydra II is located in a region of the Galactic halo that models have suggested may host material from the leading arm of the Magellanic Stream. A comparison with N-body simulations hints that the new dwarf galaxy could be or could have been a satellite of the Magellanic Clouds.
KW - Local Group
KW - Magellanic Clouds
KW - galaxies: individual (Hydra II)
UR - https://www.scopus.com/pages/publications/84928820684
UR - https://www.scopus.com/pages/publications/84928820684#tab=citedBy
U2 - 10.1088/2041-8205/804/1/L5
DO - 10.1088/2041-8205/804/1/L5
M3 - Article
AN - SCOPUS:84928820684
SN - 2041-8205
VL - 804
JO - Astrophysical Journal Letters
JF - Astrophysical Journal Letters
IS - 1
M1 - L5
ER -