MAJOR MERGERS WITH SMALL GALAXIES: THE DISCOVERY OF A MAGELLANIC-TYPE GALAXY AT z = 0.12 Based on data obtained at the WIYN facility and the Large Binocular Telescope (LBT). The LBT is an international collaboration among institutions in Germany, the United States, and Italy. LBT Corporation partners are: LBT Beteiligungsgesellschaft, Germany, representing Heidelberg University, the Max-Planck Society, and the Leibniz-Institut für Astrophysik Potsdam. The University of Arizona on behalf of the A

• Published in: The Astrophysical journal Vol. 815; no. 2
• Main Authors: Koch, Andreas, Frank, Matthias J., Pasquali, Anna, Rich, R. Michael, Rabitz, Andreas
• Format: Journal Article
• Language: English
• Published: The American Astronomical Society 15.12.2015
• Subjects: galaxies: abundances; galaxies: dwarf; galaxies: interactions; galaxies: irregular; galaxies: star formation; galaxies: structure
• ISSN: 0004-637X; 1538-4357
• DOI: 10.1088/0004-637X/815/2/105

ABSTRACT We report on the serendipitous discovery of a star-forming galaxy at redshift z = 0.116 with morphological features that indicate an ongoing merger. This object exhibits two clearly separated components with significantly different colors, plus a possible tidal stream. Follow-up spectroscopy of the bluer component revealed a low star-forming activity of 0.09 M yr−1 and a high metallicity of 12 + log(O/H) = 8.6. Based on comparison with mass-star formation-rate and mass-metallicity relations, and on fitting of spectral energy distributions, we obtain a stellar mass of 3 × 109 M , which renders this object comparable to the Large Magellanic Cloud. Thus our finding provides a further piece of evidence of a major merger already acting on small, dwarf-galaxy-like scales.