Shared star formation in the Milky Way and Magellanic Clouds

Abstract

We investigate the structural and evolutionary similarities between star formation patterns in different environments by comparing the dense clump populations in the Milky Way (MW) from the ATLASGAL survey with those from the \textit{Herschel} HERITAGE survey in the Magellanic Clouds (MCs). Our analysis reveals that MW and MC clumps behave as physical analogs, sharing consistent dust temperature distributions, mass spectra, and luminosity evolutionary trends. We establish that the warmest MC clumps and the most distant MW clumps share an identical fiducial parent structure bounded by a natural spatial scale of $\sim 1$~parsec, serving as the direct precursors to open clusters. Closer MW clumps are resolved into discrete sub-clumps, whereas colder MC clumps suffer from peripheral envelope mass blending. Furthermore, the global spatial layout of clumps in the LMC and the MW shares a remarkably similar pattern when adjusting for galaxy size, suggesting a nested, hierarchical distribution. The clump-based star formation rates are calibrated to be $\sim 0.4~M_\odot\,\rm yr^{-1}$ for the LMC and $\sim 0.1~M_\odot\,\rm yr^{-1}$ for the SMC, confirming that the LMC is currently experiencing an active, ongoing star formation burst captured within a short ($< 10^6$~yr) snapshot timescale.