Star Formation Around Supergiant Shells in the LMC

We examine the recent star formation associated with four supergiant shells (SGSs) in the Large Magellanic Cloud (LMC): LMC 1, 4, 5, and 6, which have been shown to have simple expanding-shell structures. H II regions and OB associations are used to infer star formation in the last few Myr, while massive young stellar objects (YSOs) reveal the current ongoing star formation. Distributions of ionized, H I, and molecular components of the interstellar gas are compared with the sites of recent and current star formation to determine whether triggering has taken place. We find that a great majority of the current star formation has occurred in gravitationally unstable regions, and that evidence of triggered star formation is prevalent at both large and local scales.

💡 Research Summary

This paper investigates the relationship between four supergiant shells (SGSs) in the Large Magellanic Cloud—designated LMC 1, 4, 5, and 6—and recent and ongoing star formation in their surroundings. The authors begin by confirming that each SGS exhibits a relatively simple expanding-shell morphology, with radii of several hundred parsecs and dynamical ages of roughly 10–30 Myr, based on H α,