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arXiv · 1707.05981

FOREST Unbiased Galactic plane Imaging survey with the Nobeyama 45-m telescope (FUGIN) I: Project Overview and Initial Results

Tomofumi Umemoto·Tetsuhiro Minamidani·Nario Kuno·Shinji Fujita·Mitsuhiro Matsuo·Atsushi Nishimura·Kazufumi Torii·Tomoka Tosaki·Mikito Kohno·Mika Kuriki·Yuya Tsuda·Akihiko Hirota·Satoshi Ohashi·Mitsuyoshi Yamagishi·Toshihiro Handa·Hiroyuki Nakanishi·Toshihiro Omodaka·Nagito Koide·Naoko Matsumoto·Toshikazu Onishi·Kazuki Tokuda·Masumichi Seta·Yukinori Kobayashi·Kengo Tachihara·Hidetoshi Sano·Yusuke Hattori·Sachiko Onodera·Yumiko Oasa·Kazuhisa Kamegai·Masato Tsuboi·Yoshiaki Sofue·Aya E. Higuchi·James O. Chibueze·Norikazu Mizuno·Mareki Honma·Erik Muller·Tsuyoshi Inoue·Kana Morokuma-Matsui·Hiroko Shinnaga·Takeaki Ozawa·Ryo Takahashi·Satoshi Yoshiike·Jean Costes·Sho Kuwahara
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Abstract

The FOREST Unbiased Galactic plane Imaging survey with the Nobeyama 45-m telescope (FUGIN) project is one of the legacy projects using the new multi-beam FOREST receiver installed on the Nobeyama 45-m telescope. This project aims to investigate the distribution, kinematics, and physical properties of both diffuse and dense molecular gas in the Galaxy at once by observing 12CO, 13CO, and C18O J=1-0 lines simultaneously. The mapping regions are a part of the 1st quadrant (10d < l < 50d, |b| < 1d) and the 3rd quadrant (198d < l <236d, |b| < 1d) of the Galaxy, where spiral arms, bar structure, and the molecular gas ring are included. This survey achieves the highest angular resolution to date (~20") for the Galactic plane survey in the CO J=1-0 lines, which makes it possible to find dense clumps located farther away than the previous surveys. FUGIN will provide us with an invaluable dataset for investigating the physics of the galactic interstellar medium (ISM), particularly the evolution of interstellar gas covering galactic scale structures to the internal structures of giant molecular clouds, such as small filament/clump/core. We present an overview of the FUGIN project, observation plan, and initial results, which reveal wide-field and detailed structures of molecular clouds, such as entangled filaments that have not been obvious in previous surveys, and large-scale kinematics of molecular gas such as spiral arms.

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Tomofumi Umemoto, Tetsuhiro Minamidani, Nario Kuno, Shinji Fujita, Mitsuhiro Matsuo, Atsushi Nishimura, Kazufumi Torii, Tomoka Tosaki, Mikito Kohno, Mika Kuriki, Yuya Tsuda, Akihiko Hirota, Satoshi Ohashi, Mitsuyoshi Yamagishi, Toshihiro Handa, Hiroyuki Nakanishi, Toshihiro Omodaka, Nagito Koide, Naoko Matsumoto, Toshikazu Onishi, Kazuki Tokuda, Masumichi Seta, Yukinori Kobayashi, Kengo Tachihara, Hidetoshi Sano, Yusuke Hattori, Sachiko Onodera, Yumiko Oasa, Kazuhisa Kamegai, Masato Tsuboi, Yoshiaki Sofue, Aya E. Higuchi, James O. Chibueze, Norikazu Mizuno, Mareki Honma, Erik Muller, Tsuyoshi Inoue, Kana Morokuma-Matsui, Hiroko Shinnaga, Takeaki Ozawa, Ryo Takahashi, Satoshi Yoshiike, Jean Costes, Sho Kuwahara. 2017-07-19. FOREST Unbiased Galactic plane Imaging survey with the Nobeyama 45-m telescope (FUGIN) I: Project Overview and Initial Results. https://doi.org/10.1093/pasj%2Fpsx061

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