Star Formation in Sub-Solar Metallicity Environments: Insights from the outer Galaxy and the Magellanic Clouds
Speaker: Yu Cheng (NAOJ)
Abstract:
The formation of stars in low-metallicity environments is a central problem in galaxy formation and evolution, particularly for understanding the high-redshift universe. However, studies of detailed star formation processes in such environments have been limited due to large distances and the challenge of characterizing low-mass sources. Here, I review recent progress and present observational efforts targeting the outer Galaxy and Magellanic Clouds—the nearest regions with metallicities as low as 0.2–0.5 Z☉. We conducted a multi-wavelength campaign targeting the outer Galaxy source Sh2-284, one of the lowest metallicity star-forming regions in the Milky Way. The synergy of multi-wavelength facilities, including ALMA and JWST, enables simultaneous characterization of dense gas and newly formed stellar populations. I will also present a sample study of massive young stellar objects (YSOs) in the Magellanic Clouds, followed by ALMA long-baseline observations that achieve unprecedented resolution at millimeter wavelengths (~1500 au) to probe fragmentation and kinematics. These results advance our understanding of star formation physics in conditions analogous to the early universe.