Absolute Proper Motions of H2O Masers Away from the Galactic Plane Measured with VERA in the "Superbubble" Region NGC 281

Mayumi Sato; Tomoya Hirota; Mareki Honma; Hideyuki Kobayashi; Tetsuo Sasao; Takeshi Bushimata; Yoon Kyung Choi; Hiroshi Imai; Kenzaburo Iwadate; Takaaki Jike; Seiji Kameno; Osamu Kameya; Ryuichi Kamohara; Yukitoshi Kan-ya; Noriyuki Kawaguchi; Masachika Kijima; Mi Kyoung Kim; Seisuke Kuji; Tomoharu Kurayama; Seiji Manabe; Kenta Maruyama; Makoto Matsui; Naoko Matsumoto; Takeshi Miyaji; Takumi Nagayama; Akiharu Nakagawa; Kayoko Nakamura; Chung Sik Oh; Toshihiro Omodaka; Tomoaki Oyama; Satoshi Sakai; Katsuhisa Sato; Katsunori M. Shibata; Motonobu Shintani; Yoshiaki Tamura; Miyuki Tsushima; Kazuyoshi Yamashita

doi:10.1093/pasj/59.4.743

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arXiv · 0704.3315

Absolute Proper Motions of H2O Masers Away from the Galactic Plane Measured with VERA in the "Superbubble" Region NGC 281

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Abstract

We report on absolute proper-motion measurements of an H2O maser source in the NGC 281 West molecular cloud, which is located ~320 pc above the Galactic plane and is associated with an HI loop extending from the Galactic plane. We have conducted multi-epoch phase-referencing observations of the maser source with VERA (VLBI Exploration of Radio Astrometry) over a monitoring period of 6 months since May 2006. We find that the H2O maser features in NGC 281 West are systematically moving toward the southwest and further away from the Galactic plane with a vertical velocity of ~20-30 km/s at its estimated distance of 2.2-3.5 kpc. Our new results provide the most direct evidence that the gas in the NGC 281 region on the HI loop was blown out from the Galactic plane, most likely in a superbubble driven by multiple or sequential supernova explosions in the Galactic plane.

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Mayumi Sato, Tomoya Hirota, Mareki Honma, Hideyuki Kobayashi, Tetsuo Sasao, Takeshi Bushimata, Yoon Kyung Choi, Hiroshi Imai, Kenzaburo Iwadate, Takaaki Jike, Seiji Kameno, Osamu Kameya, Ryuichi Kamohara, Yukitoshi Kan-ya, Noriyuki Kawaguchi, Masachika Kijima, Mi Kyoung Kim, Seisuke Kuji, Tomoharu Kurayama, Seiji Manabe, Kenta Maruyama, Makoto Matsui, Naoko Matsumoto, Takeshi Miyaji, Takumi Nagayama, Akiharu Nakagawa, Kayoko Nakamura, Chung Sik Oh, Toshihiro Omodaka, Tomoaki Oyama, Satoshi Sakai, Katsuhisa Sato, Katsunori M. Shibata, Motonobu Shintani, Yoshiaki Tamura, Miyuki Tsushima, Kazuyoshi Yamashita. 2007-04-25. Absolute Proper Motions of H2O Masers Away from the Galactic Plane Measured with VERA in the "Superbubble" Region NGC 281. https://doi.org/10.1093/pasj%2F59.4.743

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