Abstract Details

Name: Smitha Subramanian
Affiliation: Kavli Institute for Astronomy & Astrophysics, Peking University, Beijing, China
Conference ID: ASI2016_790
Title : Signatures of a tidally stripped stellar population from the inner regions of the Small Magellanic Cloud
Authors and Co-Authors : Richard de Grijs Kavli Institute for Astronomy & Astrophysics, Peking University, Department of Astronomy, Peking University, Beijing China) Andres Piatti (Observatorio Astronómico, Universidad Nacional de Córdoba,, Argentina) Leo Girardi (Osservatorio Astronomico di Padova - INAF, Vicolo dell'Osservatorio 5Padova, Italy) Maria Rosa Cioni (University of Hertfordshire, Physics Astronomy and Mathematics, UK; Leibnitz-Institut für Astrophysik Potsdam, Germany) Jacco van Loon (Lennard-Jones Laboratories, Keele University, UK) Ningchen Sun (Kavli Institute for Astronomy & Astrophysics, Peking University, Department of Astronomy, Peking University, Beijing, China) Benjamin Tatton (Lennard-Jones Laboratories, Keele University, UK)
Abstract Type : Oral
Abstract Category : Stars, The Milky Way Galaxy and its neighbours
Abstract : The Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC) are satellite galaxies of the Milky Way and the closest pair of interacting galaxies. The signatures of their interactions are seen in neutral HI in the form of the so-called Magellanic Bridge(MB), Magellanic Stream and the leading arm. The Magellanic Bridge is mainly a gaseous feature connecting the two galaxies, with a small fraction of in situ formed young stars. The MB is believed to be composed of tidally stripped material from the SMC during its last encounter with the LMC, approximately 200-300 Myr ago. Although predicted by tidal models, the presence of a tidally stripped old/intermediate-age stellar population in the MB is not very evident. Some previous studies have found signatures of tidally stripped stars in the outer regions (at ~4 degrees from the centre) of the eastern SMC, which may be connected to the MB. We studied the magnitude distribution of the red clumps stars using deep,near-infrared Y- and Ks-band photometric data covering ~18 squaredegrees of the SMC, comprising the main body and the galaxy's eastern wing, based on observations obtained with the VISTA Survey of the Magellanic Clouds (VMC). From this analysis, we identified regions which show a foreground population (at ~10 kpc in front of the mainbody) in the form of a distance bimodality in the red clump distribution. The most likely explanation for the origin of this feature is tidal stripping from the SMC. The homogeneous and continuous VMC data traces this feature in the direction of the MB and,particularly, identifies (for the first time) the inner region (~2.5degrees from the centre) from where the signatures of interactions start becoming evident/detectable. This result has important implications for our understanding of the nature of the interaction and the physical properties of these galaxies.