History and modes of star formation in the most active young region of the Small Magellanic Cloud, NGC 346
Tosi, M.; Sabbi, E.; Nota, A.; Gallagher, J. S.
We discuss the star formation history of the SMC region NGC 346 based on HST/ACS images. We find that NGC 346 experienced different star formation regimes in the last few Myr. This includes a dominant high density mode, with the sub-clusters hosting both pre-main sequence (PMS) and upper main sequence (UMS) stars, and a diffuse low density mode, as indicated by the presence of low-mass PMS sub-clusters.