In-situ Star Formation in the Outskirts of the Large Magellanic Cloud: Gaia DR2 Confirmation
Casetti-Dinescu, Dana I.; Girard, Terrence M.; Korchagin, Vladimir I.; van Altena, William F.; Moni Bidin, Christian; Vieira, Katherine; Mendez, Rene A.; Zhang, Lan
United States, Romania, Chile, China, Venezuela, Russia
Abstract
We explore the Gaia data release 2 (DR2) proper motions of six young, main-sequence stars, members of the Large Magellanic Cloud (LMC) reported by Moni Bidin et al. These stars are located in the outskirts of the disk, between 7° and 13° from the LMC’s center where there is very low H I content. Gaia DR2 proper motions confirm that four stars formed locally, in situ, while two are consistent with being expelled via dynamical interactions from inner, more gas-rich regions of the LMC. This finding establishes that recent star formation occurred in the periphery of the LMC, where thus far only old populations were known.