Astronomy & Astrophysics manuscript no. spec_v1_ref1_arx c ESO 2019 February 14, 2019 A Gaia DR 2 and VLT/FLAMES search for new satellites of the LMC⋆ T. K. Fritz1, 2, R. Carrera3, G. Battaglia1, 2, and S. Taibi1, 2 1 Instituto de Astrofisica de Canarias, calle Via Lactea s/n, E-38205 La Laguna, Tenerife, Spain e-mail:
[email protected] 2 Universidad de La Laguna, Dpto. Astrofisica, E-38206 La Laguna, Tenerife, Spain 3 INAF - Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, I-35122 Padova, Italy ABSTRACT A wealth of tiny galactic systems populates the surroundings of the Milky Way. However, some of these objects might actually have their origin as former satellites of the Magellanic Clouds, in particular of the LMC. Examples of the importance of understanding how many systems are genuine satellites of the Milky Way or the LMC are the implications that the number and luminosity/mass function of satellites around hosts of different mass have for dark matter theories and the treatment of baryonic physics in simulations of structure formation. Here we aim at deriving the bulk motions and estimates of the internal velocity dispersion and metallicity properties in four recently discovered distant southern dwarf galaxy candidates, Columba I, Reticulum III, Phoenix II and Horologium II. We combine Gaia DR2 astrometric measurements, photometry and new FLAMES/GIRAFFE intermediate resolution spectroscopic data in the region of the near-IR Ca II triplet lines; such combination is essential for finding potential member stars in these low luminosity systems. We find very likely member stars in all four satellites and are able to determine (or place limits on) the systems bulk motions and average internal properties.