High-mass star formation in the Large Magellanic Cloud triggered by colliding H i flows.

This article investigates the role of galactic tidal interactions in triggering high-mass star formation within the Large Magellanic Cloud (LMC) by analyzing neutral atomic hydrogen (H i) gas dynamics. It identifies three H i velocity components: the L-component (tidally driven inflow), the D-component (LMC disk), and the I-component (collision-compressed gas between L- and D-components). The study finds that approximately 74% of O-type and Wolf–Rayet (O/WR) stars are spatially associated with the I-component, supporting the scenario that collisions between the L- and D-components compress gas to form molecular clouds and subsequently high-mass stars. Detailed analyses of four star-forming regions (R136, N44, N11, and the N77–N79–N83 complex) reveal typical signatures of cloud–cloud collisions, such as complementary spatial distributions and velocity bridges, with a positive correlation between collisional gas pressure and the number of high-mass stars. The findings suggest that tidally driven colliding H i flows are a key mechanism for high-mass star formation across the LMC, with implications for understanding starburst phenomena in interacting dwarf galaxies.