Abstract
Over the last several years, various discoveries have drastically
altered our view of the iconic Magellanic Clouds (MCs), the nearest
interacting galaxy system. The best evidence is now that they are on
first infall into the Milky Way, that their stellar populations extend
much further than previously thought, and that they suffered a close
collision that tore out both the well-known Magellanic Stream and a
large amount of still undetected stellar debris. Here we propose a
community DECam survey of the Clouds mapping 480 deg^2 (distributed over
2400 deg^2 at 20% filling factor) to 24th mag griz (and u$ 23) that
will supplement the 5000 deg^2 Dark Energy Survey's partial coverage of
the Magellanic periphery, allowing us to map the expected stellar debris
and extended populations with unprecedented fidelity. We have already
conducted a pilot project demonstrating that DECam will allow us to: (1)
Map the stellar periphery of the MCs with old main-sequence turnoff
stars to a surface brightness limit of 35 mag/arcsec^2, revealing
relics of their formation and past interactions. (2) Identify the
stellar component of the Magellanic Stream and Leading Arm for the first
time, if they exist, making them the only Galactic halo tracers with
both gaseous and stellar components. (3) Derive spatially-resolved star
formation histories covering all ages out to large radii of the MCs that
will further complement our understanding of their formation. The
combination of this survey and DES data will allow us to uncover a
multitude of stellar structure that will unveil the complex and dramatic
history of these two dwarf galaxies, while enabling a broad spectrum of
community-led projects.
Original language | English |
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Pages (from-to) | 2013 |
Journal | NOAO Proposal |
Publication status | Published - Aug-2013 |