An Astrosat/UVIT FUV Survey of the Magellanic Clouds

The Magellanic System is the closest laboratory to study stellar evolution and feedback processes at low metallicity. Panoramic UVIT imaging of the Magellanic Clouds and Bridge is crucial because hot massive stars, unambiguously identified and [uniquely] characterized by far-UV (FUV) imaging, drive the chemical and dynamical evolution of galaxies, and interstellar dust cycles. Inter-comparison between the ensemble properties of hot stars and young star clusters in the 1/2, 1/5, 1/7, 1/10 Solar metallicity LMC, SMC, SMC Wing, and Bridge helps to secure our understanding of unresolved star formation activity in more distant dwarf galaxies and tidally stripped environments. We have conducted a first-look FUV.Silica (F172M) survey of the entire inner Small Magellanic Cloud (SMC) and parts of the Wing, thus securing a long-needed ∼1" resolution FUV imaging dataset for the benchmark low metallicity star-forming dwarf. An analogous program on the Large Magellanic Cloud (LMC) is currently underway, although with less complete areal coverage. These wide/shallow surveys, demonstrating detector safety, have facilitated the start of deeper multi-filter UVIT observations in select fields, similar to those obtained in peripheral regions of the SMC, which are complete down to hot main sequence stars of intermediate spectral types and enable probing hot evolved objects for the first time. We will review the status of all these UVIT surveys, describe how they complement recalibrated GALEX NUV imaging of the Clouds, and present initial scientific outcomes.