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We report the discovery of clear observational signs of past accretion/merger events in one of the Milky Way satellite galaxies, the Sextans dwarf spheroidal (dSph). These were uncovered in the spatial distribution, internal kinematics and metallicity properties of Sextans stars using literature CTIO/DECam photometric and Magellan/MMFS spectroscopic catalogues. We find the spatial distribution of stars to vary as a function of the colour/metallicity, being rather regular and round for the blue (metal-poor) red giant branch and main-sequence turn-off stars but much more elliptical and irregularly shaped for the red (metal-rich) ones, with a distinct shell-like overdensity in the northeast side. We also detect kinematic anomalies, in the form of a ring-like feature with a considerably larger systemic line-of-sight velocity and lower metallicity than the rest of stars; even the photometrically selected component with a regular looking spatial distribution displays complex kinematics. With a stellar mass of just $sim5times10^{5} M_{odot}$, Sextans becomes the smallest galaxy presenting clear observational signs of accretion to date.
Context: White dwarfs (WDs) are important and abundant tools to study the structure and evolution of the Galactic environment. However, the multiplicity of WD progenitors is generally neglected. Specifically, a merger in a binary system can lead to a
We present the deep and wide $V$ and $I_c$ photometry of the Sextans dwarf spheroidal galaxy (dSph) taken by Suprime-Cam imager on the Subaru Telescope, which extends out to the tidal radius. The colour-magnitude diagram (CMD) reaches two magnitudes
We present and discuss the stellar kinematics and populations of the S0 galaxy FCC 170 (NGC 1381) in the Fornax cluster, using deep MUSE data from the Fornax 3D survey. We show the maps of the first four moments of the stellar line-of-sight velocity
We present new XSHOOTER spectra of NLTT5306, a 0.44 $pm$ 0.04msun white dwarf in a short period (101,min) binary system with a brown dwarf companion that is likely to have previously undergone common envelope evolution. We have confirmed the presence
We present a detailed study of the stellar and HI structure of the dwarf irregular galaxies SextansA and SextansB, members of the NGC3109 association. We use newly obtained deep (r~26.5) and wide field g,r photometry to extend the Surface Brightness