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arXiv · 0801.0204

Star Formation in the Extreme Outer Galaxy: the IMF in a low metallicity environment

Chikako Yasui·Naoto Kobayashi·Alan T. Tokunaga·Masao Saito·Chihiro Tokoku
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Abstract

We are conducting a deep near-infrared (NIR) imaging survey of young embedded clusters in the extreme outer Galaxy (hereafter EOG), at the Galactic radius (R_g) of more than 18 kpc. The EOG is an excellent laboratory to study the nature of the IMF in a low-metallicity environment with a great advantage of the proximity compared to nearby dwarf galaxies, such as LMC & SMC. As a first step, we obtained deep NIR images of Digel Cloud 2 clusters at R_g ~19 kpc using the Subaru 8.2-m telescope. The observed K-band luminosity function shows that IMF in the low metallicity environment down to ~ 0.1 M_{sun} is not significantly different from the typical IMFs in the field and in the nearby star clusters as was suggested in our earlier work.

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Chikako Yasui, Naoto Kobayashi, Alan T. Tokunaga, Masao Saito, Chihiro Tokoku. 2007-12-31. Star Formation in the Extreme Outer Galaxy: the IMF in a low metallicity environment. https://arxiv.org/abs/0801.0204

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