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arXiv · 1701.05722

The VMC Survey - XXIV. Signatures of tidally stripped stellar populations from the inner Small Magellanic Cloud

Smitha Subramanian·Stefano Rubele·Ning-Chen Sun·Léo Girardi·Richard de Grijs·Jacco Th. van Loon·Maria-Rosa L. Cioni·Andrés E. Piatti·Kenji Bekki·Jim Emerson·Valentin D. Ivanov·Leandro Kerber·Marcella Marconi·Vincenzo Ripepi·Benjamin L. Tatton
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Abstract

We study the luminosity function of intermediate-age red-clump stars using deep, near-infrared photometric data covering $\sim$ 20 deg$^2$ located throughout the central part of the Small Magellanic Cloud (SMC), comprising the main body and the galaxy's eastern wing, based on observations obtained with the VISTA Survey of the Magellanic Clouds (VMC). We identified regions which show a foreground population ($\sim$11.8 $\pm$ 2.0 kpc in front of the main body) 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 rather than the extended stellar haloes of the Magellanic Clouds and/or tidally stripped stars from the Large Magellanic Cloud. The homogeneous and continuous VMC data trace this feature in the direction of the Magellanic Bridge and, particularly, identify (for the first time) the inner region ($\sim$ 2 -- 2.5 kpc from the centre) from where the signatures of interactions start becoming evident. This result provides observational evidence of the formation of the Magellanic Bridge from tidally stripped material from the SMC.

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Smitha Subramanian, Stefano Rubele, Ning-Chen Sun, Léo Girardi, Richard de Grijs, Jacco Th. van Loon, Maria-Rosa L. Cioni, Andrés E. Piatti, Kenji Bekki, Jim Emerson, Valentin D. Ivanov, Leandro Kerber, Marcella Marconi, Vincenzo Ripepi, Benjamin L. Tatton. 2017-01-20. The VMC Survey - XXIV. Signatures of tidally stripped stellar populations from the inner Small Magellanic Cloud. https://doi.org/10.1093/mnras%2Fstx205

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