The Magellanic Edges Survey IV. Complex tidal debris in the SMC outskirts

TL;DR

This study uses Magellanic Edges Survey data combined with Gaia EDR3 to analyze the complex tidal debris in the outskirts of the Small Magellanic Cloud, revealing multiple stellar populations and evidence of recent tidal stripping by the LMC.

Contribution

It provides new insights into the stellar populations and tidal debris in the SMC outskirts, highlighting the presence of a perturbed, metal-rich population likely resulting from recent tidal interactions.

Findings

Identification of two distinct stellar populations in the SMC outskirts.

The perturbed population is more metal-rich and located ~7 kpc in front of the main SMC.

Evidence suggests the perturbed stars are debris from tidal stripping by the LMC.

Abstract

We use data from the Magellanic Edges Survey (MagES) in combination with Gaia EDR3 to study the extreme southern outskirts of the Small Magellanic Cloud (SMC), focussing on a field at the eastern end of a long arm-like structure which wraps around the southern periphery of the Large Magellanic Cloud (LMC). Unlike the remainder of this structure, which is thought to be comprised of perturbed LMC disk material, the aggregate properties of the field indicate a clear connection with the SMC. We find evidence for two stellar populations in the field: one having properties consistent with the outskirts of the main SMC body, and the other significantly perturbed. The perturbed population is on average ~0.2 dex more metal-rich, and is located ~7 kpc in front of the dominant population with a total space velocity relative to the SMC centre of ~230 km/s broadly in the direction of the LMC. We speculate on possible origins for this perturbed population, the most plausible of which is that it comprises debris from the inner SMC that has been recently tidally stripped by interactions with the LMC.