研究者業績
  1. 研究者検索結果一覧
  2. 土居 明広

土居 明広

ドイ アキヒロ  (Akihiro DOI)

基本情報

所属
国立研究開発法人宇宙航空研究開発機構 宇宙科学研究所 宇宙物理学研究系 助教
総合研究大学院大学 物理科学研究科 宇宙科学専攻 助教
学位
博士 (理学)(2005年3月 東京大学)
研究者番号
90403641
ORCID ID
 https://orcid.org/0000-0003-4384-9568
J-GLOBAL ID
201101033666007265
researchmap会員ID
B000004312

研究キーワード

 11

研究分野

 3

経歴

 3

論文

 121
  • Makoto Arimoto, Akihiro Doi, Hatsune Goto, Shuichi Gunji, Junko S. Hiraga, Daiki Ishi, Tatsuro Kanenaga, Shogo Kobayashi, Ryuji Kondo, Natsuki Kurooka, Akito Kutsumi, Junpei Kuwabara, Tomoki Kuwahara, Yoshitomo Maeda, Hideo Matsuhara, Tatehiro Mihara, Akihiro Miyasaka, Hiroshi Murakami, Yuuya Nagase, Isshin Nagataka, Hiroshi Nakajima, Haruaki Niinuma, Kumiko K. Nobukawa, Masayoshi Nobukawa, Naoki Ogino, Hiro Otsuka, Tenshin Otsuka, Takanori Sakamoto, Tatsuya Sawano, Motoko Serino, Hsien-chieh Shen, Satoshi Sugita, Mutsumi Sugizaki, Takaaki Tanaka, Takumi Togashi, Hiroshi Tomida, Hiroyuki Uchida, Shutaro Ueda, Keito Watanabe, Daisuke Yonetoku, Tomokage Yoneyama, Kazuki Yugi
    Journal of Astronomical Telescopes, Instruments, and Systems 12(02) 2026年5月22日  
  • Hatsune Goto, Isshin Nagataka, Daisuke Yonetoku, Daiki Ishi, Yoshitomo Maeda, Hsien-Chieh Shen, Ryuji Kondo, Akito Kutsumi, Hiroshi Tomida, Makoto Arimoto, Shutaro Ueda, Tatsuya Sawano, Keito Watanabe, Haruaki Niinuma, Takumi Togashi, Rinon Kageyama, Tatsuro Kanenaga, Tenshin Otsuka, Junpei Kuwabara, Motoko Serino, Yuta Yamamoto, Kanta Yagi, Kaita Nakahashi, Kenta Kanou, Satoshi Sugita, Yuya Nagase, Naoki Takase, Shunichi Nakatsubo, Shuichi Gunji, Akihiro Doi, Hideo Matsuhara, Toru Kaga
    Journal of Astronomical Telescopes, Instruments, and Systems 12(01) 2026年3月26日  
  • Daisuke Yonetoku, Akihiro Doi, Tatehiro Mihara, Hideo Matsuhara, Takanori Sakamoto, Kohji Tsumura, Kunihito Ioka, Makoto Arimoto, Yoshiyuki Ando, Teruaki Enoto, Kenjiro Fujimoto, Hatsune Goto, Junko Hiraga, Nobuyuki Kawai, Ryuji Kondo, Shunsuke Kurosawa, Yoshitomo Maeda, Ikuyuki Mitsuishi, Toshio Murakami, Issin Nagataka, Yujin Nakagawa, Hiroshi Nakajima, Naoki Ogino, Masataka Sato, Tomoya Sato, Tatsuya Sawano, Motoko Serino, Hsien-Chieh Shen, Satoshi Sugita, Mutsumi Sugizaki, Shuta Takahashi, Toru Tamagawa, Keisuke Tamura, Takaaki Tanaka, Toru Tanimori, Makoto S. Tashiro, Hiroshi Tomida, Hiroyuki Uchida, Shutaro Ueda, Kazutaka Yamaoka, Makoto Yamauchi, Yoichi Yatsu, Atsumasa Yoshida, Hiroshi Akitaya, Akihiko Fukui, Haruki Fukui, Ryo Hashimoto, Tomoya Hori, Yoshifusa Ita, Rinon Kageyama, Koji Kawabata, Shuji Matsuura, Akihiro Miyasaka, Kentaro Motohara, Norio Narita, Hirofumi Noda, Hirofumi Okita, Kei Sano, Keisuke Shinozaki, Sou Tajima, Yuji Urata, Takehiko Wada, Hayato Yamashita, Kenshi Yanagisawa, Michitoshi Yoshida, Shuichi Gunji, Takumi Togashi, Ryuji Sato, Keito Watanabe, Haruaki Niinuma, Nobutaka Bando, Ichiro Jikuya, Kenji Minesugi, Yasuyuki Miyazaki, Yusuke Kono, Naoki Takase, Shinichi Nakatsubo, Tooru Kaga, Katsuaki Asano, Kohei Inayoshi, Susumu Inoue, Hirotaka Ito, Hideyuki Izumiura, Norita Kawanaka, Tomoya Kinugawa, Shota Kisaka, Kenta Kiuchi, Koutarou Kyutoku, Jin Matsumoto, Akira Mizuta, Kohta Murase, Hiroki Nagakura, Shigehiro Nagataki, Yoshikazu Nakada, Takashi Nakamura, Yuu Niino, Yudai Suwa, Keitaro Takahashi, Takahiro Tanaka, Kenji Toma, Tomonori Totani, Ryo Yamazaki, Jun'ichi Yokoyama, Yuichi Harikane, Masaomi Tanaka, Shigeo S. Kimura, Mariko Kimura, Hiroya Umeda
    JOURNAL OF ASTRONOMICAL TELESCOPES INSTRUMENTS AND SYSTEMS 11(4) 75-75 2025年10月1日  査読有り
  • Kohji Tsumura, Hideo Matsuhara, Koji S. Kawabata, Hiroshi Akitaya, Shuji Matsuura, Haruki Fukui, Rinon Kageyama, Akito Masuko, Akihiro Miyasaka, Keisuke Shinozaki, Takehiko Wada, Hirofumi Noda, Yoshifusa Ita, Tomoyasu Yamamuro, Hiroshi Tomida, Akihiro Doi, Daisuke Yonetoku
    JOURNAL OF ASTRONOMICAL TELESCOPES INSTRUMENTS AND SYSTEMS 11(3) 2025年7月1日  査読有り
  • Kazunori Akiyama, Kotaro Niinuma, Kazuhiro Hada, Akihiro Doi, Yoshiaki Hagiwara, Aya Higuchi, Mareki Honma, Tomohisa Kawashima, Dimitar Kolev, Shoko Koyama, Sho Masui, Ken Ohsuga, Hidetoshi Sano, Hideki Takami, Yuh Tsunetoe, Yoshinori Uzawa, Takuya Akahori, Yuto Akiyama, Peter Galison, Takayuki J. Hayashi, Tomoya Hirota, Makoto Inoue, Yuhei Iwata, Michael Johnson, Motoki Kino, Yutaro Kofuji, Yosuke Mizuno, Kotaro Moriyama, Hiroshi Nagai, Kenta Nakamura, Shota Notsu, Fumie Ono, Yoko Oya, Tomoaki Oyama, Hannah Rana, Hiromi Saida, Ryo Saito, Yoshihiko Saito, Mahito Sasada, Satoko Sawada-Satoh, Mikiya M. Takahashi, Mieko Takamura, Edward Tong, Hiroyuki Tsuji, Shogo Yoshioka, Yoshimasa Watanabe
    Space Telescopes and Instrumentation 2024: Optical, Infrared, and Millimeter Wave 91-91 2024年8月23日  
もっとみる

MISC

 102
  • Hiroshi Nagai, Makoto Inoue, Keiichi Asada, Seiji Kameno, Akihiro Doi
    Astrophys.J.648:148-157,2006 2006年5月12日  
    We present a study of the kinematic and spectral ages of the Gigahertz-Peaked<br /> Spectrum (GPS) source CTD~93. Measurements of the hot spot separation over 8.5<br /> yr show evidence of an increase. The separation rate along the source axis is<br /> 0.34$\pm0.11c$ (H$_{0}$=72 km s$^{-1}$ Mpc$^{-1}$), which results in a<br /> kinematic age of 2200$\pm$700 yr. Assuming that two hot spots are moving apart<br /> at equal speeds, we derive an advance speed of 0.17$\pm0.06c$. The radio lobe<br /> spectra show a high frequency steepening, as expected if energetic electrons<br /> lose energy by synchrotron radiation. The spectral break decreases with the<br /> distance from the hot spot in the northern component of CTD~93. This tendency<br /> is expected from the basic scenario of radio lobe evolution involving particle<br /> acceleration at the hot spots, with the radio lobes populated by high energy<br /> electrons which have leaked from the hot spots. Although a core-jet morphology<br /> for CTD~93 has previously been proposed, these results indicate that the<br /> morphology is similar to that of Compact Symmetric Object (CSO). From the<br /> spectral fits in the northern component we found a break frequency of 3.7 GHz<br /> at the edge of the lobe. The resultant spectral age is $\sim$300 yr assuming<br /> the equipartition magnetic field. This requires the advance speed of 0.26$c$,<br /> which shows a good agreement of the hot spot motion of 0.17$\pm0.06c$. Our<br /> results strongly support the hypothesis that CSOs are young radio sources.
  • Takumi Nagayama, Koji Takeda, Toshihiro Omodaka, Hiroshi Imai, Seiji Kameno, Yoshiaki Sofue, Akihiro Doi, Kenta Fujisawa, Asao Habe, Mareki Honma, Mareki Honma, Noriyuki Kawaguchi, Noriyuki Kawaguchi, Eiji Kawai, Hideyuki Kobayashi, Hideyuki Kobayashi, Yasuhiro Koyama, Yasuhiro Murata, Yasuhiro Murata, Kazuo Sorai, Hiroshi Sudou, Hiroshi Takaba, Sayaka Tamura, Sayaka Tamura, Ken Ichi Wakamatsu
    Publications of the Astronomical Society of Japan 60 1069-1075  
    We present the proper motions of H2O masers in NML Cygni, observed with the Japanese VLBI Network at three epochs spanning 455 d. We detected about 15 maser features at each epoch. Overall, 13 features that were detected at least twice were tracked by their radial velocities and proper motions. The three-dimensional kinematics of the maser features indicate the presence of an expanding outflow. The major axis of the outflow is estimated to be at a position angle of ∼ 108°, and an inclination angle of ∼ 8° with respect to the line of sight. The H2O masers are located between an apparent minimum radius of ∼ 9.6 × 1012 m (64 AU) and a maximum radius of ∼ 3.0 × 1013 m (202AU), where the expansion velocity increases from 12 to 27 km s-1. A comparison with the distributions of SiO, H2O, and OH masers suggests that the outflow of NML Cygni is expanding outside a radius of ∼ 1.5 × 10 13 m (100 AU). This radius corresponds to 6 stellar radii, and is consistent with the radius of the inner boundary for the dust shell. © 2008. Astronomical Society of Japan.

講演・口頭発表等

 29
もっとみる

共同研究・競争的資金等の研究課題

 12
もっとみる
一覧へ戻る