Published Papers - TOMITA Akihiko

An Analysis of Peer-Reviewed Papers on Astronomy Education Published From 2007 to 2019 in Japan

Akihiko Tomita, Hidehiko Agata, Shigeyuki Karino, Naoki Matsumoto, Junya Terazono （Part： Lead author )

Astronomy Education Conference: Bridging Research & Practice, the proceedings of AstroEdu Meeting 2019, organized by IAU Commission C1 Astronomy Education and Development and IAU Commission C1 Working Group Astronomy Education Research and Methods, ed. Paulo S. Bretones, Urban Eriksson, Pedro Russo, ISBN/EAN: 978-94-91760-21-1     46 - 53   2021.03  [Refereed]

The Gateway Science: a Review of Astronomy in the OECD School Curricula, Including China and South Africa

Saeed Salimpour, Sophie Bartlett, Michael T. Fitzgerald, David H. McKinnon, K. Ross Cutts, C. Renee James, Scott Miller, Lena Danaia, Robert P. Hollow, Sergio Cabezon, Michel Faye, Akihiko Tomita, Charles Max, Michael de Korte, Cyrille Baudouin, Daina Birkenbauma, Maria Kallery, Sara Anjos, Qixuan Wu, Hye-eun Chu, Eileen Slater, and Amelia Ortiz-Gil

Research in Science Education     2020  [Refereed]

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DOI: https://doi.org/10.1007/s11165-020-09922-0

Daily life astronomy activity and its contribution to children and educators in science education

Akihiko Tomita （Part： Lead author )

EPJ Web of Conferences, The International Symposium on Education in Astronomy and Astrobiology (ISE2A 2017), Utrecht, the Netherlands, July 3-7, 2017, S. Deustua, K. Eastwood and I. Loes Ten Kate (Eds.)   200   2019.02  [Refereed]

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DOI: 10.1051/epjconf/201920002002

Expert teachers' views of factors influencing their teaching quality in early childhood science in Japan

Akihiko Tomita, Maria Kallery

Electronic Proceedings of the ESERA 2015 Conference. Science education research: Engaging learners for a sustainable future     2585 - 2591   2016  [Refereed]

Evening Sky Watching for Students: Let's observe the evening sky with the naked eye

Akihiko Tomita （Part： Lead author )

astroEDU     2016  [Refereed]

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DOI: 10.14586/astroedu/1616

天文教育の正の向きと逆の向き

富田晃彦 （Part： Lead author,　Corresponding author )

天文教育   37 ( 2 ) 14 - 15   2025.03

Astronomy Day in Schools project : Feedback from participating students and teachers

Akihiko Tomita （Part： Lead author,　Corresponding author )

和歌山大学教育学部紀要 自然科学   75   1 - 10   2025.02  [Refereed]

DOI

Elementary school classes reevaluated from a STEAM education point of view

富田晃彦, 久保文人, 角谷和杜, 上田 恵, 田中伸一 （Part： Lead author )

和歌山大学教職大学院紀要「学校教育実践研究」   ( 9 ) 29 - 33   2024.11  [Refereed]

DOI

"Little Scientists" of the young Z generation boarded the GALAXY CRUISE

Akihiko Tomita, Kumiko Usuda-Sato （Part： Lead author,　Corresponding author )

Global Hands-On Universe 2023: Kagoshima where Polaris is seen in low sky     5 - 8   2024.10

Exploring the current issues of public astronomical observatories in Wakayama Prefecture: A case study of Kimino Town Misato Astronomical Observatory and Kawabe Astronomical Observatory

Koki Sawada, Tatsuki Yonezawa, Hiroaki Akiyama, Akihiko Tomita, Yusuke Sato, Miyuki Hayashi

Tourism Studies ( Wakayama University Association for Tourism Studies )  ( 31 ) 15 - 31   2024.09  [Refereed]

DOI

The Astronomy Day in Schools project: linking astronomy, culture, society and daily life, for establishing the new Silk Road

Akihiko Tomita, Paulo Sergio Bretones, Boonrucksar Soonthornthum （Part： Lead author,　Corresponding author )

Astronomy Education Journal ( Our Solar Siblings )  AstroEdu Conference 2023 Proceedings   aecon23-102aepp-1 - aecon23-102aepp-2   2024.08  [Refereed]

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Astronomy Day in Schools (ADiS) is a new project to share practices of astronomy education worldwide. The ADiS is unique in that it has quarterly online meetings, and that it focuses on equinoxes and solstices. This paper describes the launch and development of the ADiS.

DOI

高校初年度理科総合必修科目の検討：教員養成での問題と聞き取り

富田晃彦, 縣 秀彦, 石原 諭, 亀田直記, 都築 功, 夏目雄平, 此松昌彦 （Part： Lead author )

和歌山大学教育学部紀要, 自然科学   74   9 - 16   2024.02

Evaluating Circulation of Peer-reviewed Articles in Astronomy Education and Outreach

鴈野重之, 富田晃彦

Japanese Journal of Science Communication   ( 33 ) 49 - 57   2023.09  [Refereed]

DOI

すばる望遠鏡のビッグデータを用いた教材の開発と利用の提案：広大な銀河宇宙を教室に

原 正, 冨樫民樹, 平塚雄一郎, 臼田-佐藤功美子, 富田晃彦

みんなの地学   ( 4 ) 1 - 6   2023.07

生徒と共に、われら地球人：国境を越えて協働してみよう、共有してみよう

富田晃彦 （Part： Lead author )

理科教室 ( 科学教育研究協議会 )  66 ( 5 ) 35 - 39   2023.05  [Invited]

学校天文の日 Astronomy Day in Schools：児童生徒教員ネットワークの国際ネットワーク作り

富田晃彦 （Part： Lead author )

天文教育   35 ( 2 ) 22 - 25   2023.03

ばねのおもちゃを使ったケプラーの第3法則理解のための教材開発

磯合竜弥, 富田晃彦

天文教育   35 ( 2 ) 4 - 7   2023.03

Change in Attitude of Participants Observed in Astronomy Education and Outreach with Apra

Sachiyo Uenoyama, Akihiko Tomita （Part： Last author )

Bulletin of the Faculty of Education, Wakayama University, Natural Science   ( 73 ) 17 - 26   2023.02  [Refereed]

実験操作技能の向上を目指した理科の授業開発：ルーブリックと動画教材の比較

松尾佑樹, 富田晃彦

和歌山大学教職大学院紀要「学校教育実践研究」   ( 6 ) 105 - 115   2022.03  [Refereed]

小学校への出前授業を通して考える校種間横断的な小・中学校理科授業づくり：王寺町立王寺南義務教育学校開校に向けて

新明郁実, 富田晃彦

和歌山大学教職大学院紀要「学校教育実践研究」   ( 6 ) 139 - 145   2022.03  [Refereed]

小中学校の学校教員が天文分野の授業の際に知っておきたいこと

富田晃彦 （Part： Lead author )

第35回 天文教育研究会 集録     131 - 134   2021.11

5.26 皆既月食を利用した高校生共同観測：月の視差から距離を求める

岸本 浩, 横山昌弘, 加瀬部 久司, 富田晃彦

第35回 天文教育研究会 集録     139 - 142   2021.11

IAU 天文教育コーディネーター WG 報告

富田晃彦, 鴈野重之, 木村かおる, 前田昌志, 松本直記, 縣 秀彦, 矢治 健太郎, 亀谷和久, 篠原秀雄 （Part： Lead author )

第35回 天文教育研究会 集録     183 - 184   2021.11

イランの正月＝春分「ノウルーズ」に合わせた日本とイランと世界の交流

富田晃彦, 綾仁一哉, 山岡均 （Part： Lead author )

天文教育   33 ( 5 ) 4 - 7   2021.09

皆既月食での高校生共同観測の顛末と今後：月の視差から距離を求める

岸本浩, 横山昌弘, 加瀬部久司, 富田晃彦

天文教育   33 ( 5 ) 53 - 54   2021.09

IAU が取り組む天文教育・アウトリーチの動向

富田晃彦 （Part： Lead author )

天文月報   114 ( 9 ) 553 - 562   2021.09  [Invited]

2020年夏のワークショップを振り返って：リモート時代に発見したうれしい三つのショーシャルの密

富田晃彦 （Part： Lead author )

理科の教育 ( 日本理科教育学会、東洋館出版社 )  70 ( 828 )   2021.07

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「特集：ポストコロナの理科授業；公開ワークショップの所感と自身の実践」の中の一記事

Stories of Tomorrow: Practice in Elementary School and Its Reflection

Akihiko Tomita, Fumihito Kubo, Masashi Maeda, Rosa Doran （Part： Lead author )

Bulletin of Course Specializing in Professional Development in Education, Wakayama University ( 和歌山大学大学院教育学研究科教職開発専攻(教職大学院) )  ( 5 ) 113 - 118   2021.03  [Refereed]

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日本語版（pp.113-118）と英語版（pp.E1-E8）の両方をオンラインで公開している。

Rocket Girls Training Course Initiatives and Achievements

SATO Yoshiko, TOMITA Akihiko, AKIYAMA Hiroaki

Proceedings of the Annual Meeting of Japan Society for Science Education ( Japan Society for Science Education )  45   455 - 457   2021

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科学技術分野への女性の参入増加は科学技術の発展においては必要不可欠であり，女子の理系進路選択支援は大変重要である.私立女子校である和歌山信愛中学校高等学校は，和歌山大学と連携し当校の女子高校生を対象とした「ロケットガール養成講座」を毎年実施している.本講座は全長約140 cm，重量約7 kgの本格的なロケットの設計・製作から，その打上げに至るまで，すべて女子高校生自身の手で実現していく企画である.ロケットの製作・打上という高度で複雑なプロジェクトを通じ，理工系の技術を学びながら，生徒自身が問題点を発見し理工系の楽しさを実感すること，また技術のみならずプロジェクトマネジメントやチームワークを学ぶことを本講座のねらいとしている.約10年間における本講座の実施を通じ，本講座は女子の理系進路選択支援として大いに有効であると考えられる．受講生の意識や行動の変容についても定量的な評価法を検討中である．

DOI

Report of WG on IAU Astronomy Education Coordinator in Japan: Starting up

富田晃彦, 縣秀彦, 鴈野重之, 木村かおる, 松本直記, 前田昌志 （Part： Lead author )

天文教育研究会・日本天文教育普及研究会年会集録   34th-2020   2020.11

International Astronomy Teacher-Training Program NASE Course in Japan

Akihiko Tomita, Sachiyo Uenoyama, Kanae Sagisaka, Takashi Nakakushi, Jun Fukue, Katsura Matsumoto （Part： Lead author )

The Astronomical Herald   113 ( 8 ) 497 - 502   2020.08

国際教員研修プログラムNASE：ワークショップ8「宇宙の膨張」

福江純, 上之山幸代, 鷺坂奏絵, 富田晃彦, 中串孝志, 松本桂

天文教育   32 ( 4 ) 25 - 29   2020.07

国際教員研修プログラムNASE：NASE-Japan 2019 の評価

富田晃彦, 上之山幸代, 鷺坂奏絵, 中串孝志, 福江純, 松本桂 （Part： Lead author )

天文教育   32 ( 4 ) 43 - 68   2020.07

国際教員研修プログラムNASE：ワークショップ9「惑星と系外惑星」

中串孝志, 上之山幸代, 鷺坂奏絵, 富田晃彦, 福江純, 松本桂

天文教育   32 ( 4 ) 30 - 38   2020.07

大学生の天文に対するイメージ調査：大学生は何で天文用語を知ってきたのか

西川聖哲, 江口尚輝, 備中綾, 玉置将之, 富田晃彦, 中串孝志, 尾久土正己

天文教育   32 ( 4 ) 9 - 16   2020.07

手作り簡易分光器の改良：利き目の問題と可変スリット

井口楓梨, 宇野和行, 富田晃彦

天文教育   32 ( 4 ) 2 - 8   2020.07

国際教員研修プログラムNASE：ワークショップ10「天体観測をしよう」

中串孝志, 上之山幸代, 鷺坂奏絵, 富田晃彦, 福江純, 松本桂

天文教育   32 ( 4 ) 39 - 42   2020.07

国際教員研修プログラムNASE：ワークショップ5「太陽黒点と太陽スペクトル・星のスペクトル」

福江純, 上之山幸代, 鷺坂奏絵, 富田晃彦, 中串孝志, 松本桂

天文教育   32 ( 3 ) 38 - 42   2020.05

国際教員研修プログラムNASE：ワークショップ7「目に見えない光」

松本桂, 上之山幸代, 鷺坂奏絵, 富田晃彦, 中串孝志, 福江純

天文教育   32 ( 3 ) 49 - 54   2020.05

簡易四分儀を用いた理科と数学科での教科間連携を図った授業実践：中学校理科「宇宙の中の地球」、中学校数学「三平方の定理」の分野を通して

新明郁実, 富田晃彦

天文教育   32 ( 3 ) 10 - 13   2020.05

国際教員研修プログラムNASE：ワークショップ6「星の一生」

松本桂, 上之山幸代, 鷺坂奏絵, 富田晃彦, 中串孝志, 福江純

天文教育   32 ( 3 ) 43 - 48   2020.05

国際教員研修プログラムNASE：ワークショップ4「天文教育なんでも教具」

上之山幸代, 鷺坂奏絵, 富田晃彦, 中串孝志, 福江 純, 松本 桂

天文教育   32 ( 3 ) 32 - 37   2020.05

国際的な天文分野教員研究 NASE の実施：経緯と改善への振り返り

富田晃彦

和歌山大学教職大学院紀要「学校教育実践研究」   ( 4 ) 97 - 104   2020.03  [Refereed]

国際教員研修プログラムNASE：ワークショップ1「太陽の動き：地平線と日時計」

富田晃彦, 上之山幸代, 鷺坂奏絵, 中串孝志, 福江 純, 松本 桂 （Part： Lead author )

天文教育   32 ( 2 ) 49 - 54   2020.03

国際教員研修プログラムNASE：ワークショップ3「月食と日食」

富田晃彦, 上之山幸代, 鷺坂奏絵, 中串孝志, 福江 純, 松本 桂 （Part： Lead author )

天文教育   32 ( 2 ) 59 - 67   2020.03

国際教員研修プログラムNASE：NASE-Japan 2019 の概観と開催の経緯

富田晃彦, 上之山幸代, 鷺坂奏絵, 中串孝志, 福江 純, 松本 桂 （Part： Lead author )

天文教育   32 ( 2 ) 42 - 48   2020.03

国際教員研修プログラムNASE：ワークショップ2「天球：星と太陽と月の動きの模型」

鷺坂奏絵, 上之山幸代, 富田晃彦, 中串孝志, 福江 純, 松本 桂

天文教育   32 ( 2 ) 55 - 58   2020.03

文化と社会に力を与える「星空案内」の環境についての一考察：フィリピン・ネグロス島での実践の振り返りから

上之山幸代, 富田晃彦, 鷺坂奏絵

和歌山大学教育学部紀要, 人文科学   70   53 - 63   2020.02

天文教育におけるカリキュラムの比較：学習指導要領、NASE、星のソムリエ®の比較を通して

鷺坂奏絵, 富田晃彦, 上之山幸代

和歌山大学教育学部紀要, 自然科学   70   17 - 24   2020.02

国際化時代の地域天体観望会：大阪日本語教育センターでの実践例

富田晃彦, 上之山幸代, 鷺坂奏絵

和歌山大学教育学部紀要, 教育科学   70   83 - 88   2020.02

Comparison of Astronomy School Education Curricula Between Philippines and Japan

Lieza Crisostomo, Sachiyo Uenoyama, Kanae Sagisaka, Akihiko Tomita

Latin-American Journal of Astronomy Education   ( 29 ) 87 - 102   2020  [Refereed]

21 Years Activity of the ITAU Activities

Hasan Baghbani, Mahdi Rokni, Akihiko Tomita, Maryam Hadizadeh

Proceedings of the International Astronomical Union ( Cambridge University Press ({CUP}) )  15 ( S367 ) 512 - 513   2019.12  [Refereed]

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<title>Abstract</title>ITAU, the Iranian teacher’s astronomy union, has attempted for many years to introduce astronomy to the teachers and students not only in Iran but also around the world by providing various materials and projects. The primary goal of ITAU is also to protect the environment with a help of students; therefore, first, try to change the attitude of students. SINA, Student’s International Network for Astronomy, will follow the goals.

DOI

Integrated Active Learning Utilizing the Stories of Tomorrow at Elementary School in Japan

Akihiko Tomita, Fumihito Kubo, Masashi Maeda, Rosa Doran （Part： Lead author )

Proceedings of the International Astronomical Union ( Cambridge University Press ({CUP}) )  15 ( S367 ) 423 - 424   2019.12  [Refereed]

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<title>Abstract</title>In 2018, two schools from Japan participated in Stories of Tomorrow, a computer-based STEAM educational practice for primary school students. We were able to learn from the students’ feedback that through problem-solving, a spirit of collaboration, a spirit of overcoming failure, and a deep understanding of scientific research and technology development have been nurtured. We also confirmed the importance of translation and coordination to cross over the language barrier.

DOI

Tanabata Star Festival

Akihiko Tomita （Part： Lead author )

NASE kaleidoscope of experiences in cultural astronomy: Archeoastronomy and Astronomy in the City, Proceedings of the Second Seminar on NASE Experiences in Cultural Astronomy, Vienna, Austria, 24 August 2018, ed. Rosa M. Ros and Juan A. Belmonte     189 - 191   2018.09

The Star-Sommelier Has Opened a New Way for a Wider Astronomy Communication

Shinpei Shibata, Masaki Kouda, Eri Watanabe, Kyohei Ando, Akihiko Tomita, Masahiro Mizutani, Kouichi Wada, Kozue Uriu and on behalf of the organization of the qualification system for the astronomy guidehin-ya Narusawa, Mitsumi Fujishita, Hiroki Akisawa, Kenta Fujisawa, Yasuhide Fujita, Takahiro Fukuzumi, Hiromi Funakoshi, Hiroyuki Geshiro, Hideo Hara, Kenji Hashimoto, Tsutomu Hayamizu, Ryo Iizuka, Kazumasa Imai, Takeshi Inoue, Masayuki Kagami, Kazuhisa Kageyama, Takeshi Kamitamari, Masahiro Koishikawa, Shouta Maeno, Hidehiko Matsuo, Takashi Miyamoto, Masaki Morimoto, Hiroyuki Naito, Sumio Nakane, Takeshi Nakashima, Masami Okyudo, Takaaki Oribe, Takaaki Ozeki, Makoto Sakamoto, Yasuo Sano, Naoko Sato, Masayuki Tachikawa, Yoshimasa Tai, Setsuro Takahara, Yoshitaka Takahashi, Mikimasa Takeuchi, Naoto Tatsumi, Shinji Toyomasu, Naoki Toyoshima, Makoto Watanabe, Takeshi Yada, Ryoji Yamada, Michinari Yamamoto, Hideyo Yokotsuka

Proceedings of the International Conference CAP2018, Communicating Astronomy with the Public 2018, 24-28 March 2018, Fukuoka, Japan     222 - 223   2018.07

The Assessment of "Fun and Play" Visiting Activity for Young Children

Akihiko Tomita

roceedings of the International Conference CAP2018, Communicating Astronomy with the Public 2018, 24-28 March 2018, Fukuoka, Japan     149 - 149   2018.07

和歌山大学教育学部屋上天文台で得られた天体映像を使った中学生への授業実践

富田晃彦 （Part： Lead author )

和歌山大学教育学部紀要   68 ( 1 ) 30 - 39   2018.01

教員養成での学生教育とサイエンスコミュニケーション

富田晃彦

日本サイエンスコミュニケーション協会誌   7 ( 1 ) 6 - 9   2017.05  [Invited]

University and Junior High School Students' Understanding of the Sun's Diurnal Motion and their Writing Ability

廣木義久, 藤井宏明, 富田晃彦

大阪教育大学紀要 第V部門 教科教育 ( 大阪教育大学 )  65 ( 2 ) 23 - 31   2017.02

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太陽の日周運動に関する理解度と文章記述能力について大学生と中学生を対象に調査した。太陽の軌跡に関する図の分析から,大学生において天球という概念が理解できていない者がいること,大学生と中学生の多くが北極点における方位を理解できていないことが分かった。また,太陽の軌跡に関する文章の分析から,記述のために必要な要素が不足しているケースが多いことが明らかとなった。本研究の結果から,大学生,中学生ともに科学的な文章を正確に記述することに対する意識が低いことが明らかとなった。理科授業の中で,科学的な文章を記述させて間違いを訂正させたりする場面を設定するなどして,科学的な文章を正しく記述できるようにすることが求められる。We examined university and junior high school students' understanding of the Sun's diurnal motion and their writing ability. An analysis of students' illustrations on the Sun's diurnal motion revealed that some university students did not understand the concept of the celestial sphere and that many university and junior high school students did not understand the southward directions at the North Pole. Furthermore, an analysis of students' sentences on the Sun's diurnal motion revealed many insufficient descriptions for the accurate explanation. The results of the analyses suggested that both university and junior high school students had little awareness regarding accurate descriptions in scientific writing. Therefore, we propose that further training needs to be provided to students for scientific writing in science classes.

Essence of Physics at Secondary School Science Education

顧 萍, 井嶋 博, 石塚 亙, 木曽田 賢治, 富田 晃彦

和歌山大学教育学部紀要. 教育科学 = Bulletin of the Faculty of Education, Wakayama University. 和歌山大学教育学部紀要委員会 編 ( 和歌山大学教育学部 )  67   101 - 104   2017.02

DOI

Teacher's Training to Overcome the Disinterest in Physics and Earth Science

TOMITA Akihiko

TRENDS IN THE SCIENCES ( Japan Science Support Foundation )  22 ( 1 ) 1_52 - 1_54   2017

DOI

The History of 10 Years of the Misato 8m Radio Telescope

Sato Naoko, Okyudo Masami, Tomita Akihiko, Yadomaru Yasushi

和歌山大学宇宙教育研究所紀要   5   33 - 50   2016.03

DOI

Astronomy for Development; Approaches in Asia

Kumiko Usuda-Sato, Akihiko Tomita

Publications of the Korean Astronomical Society (Proceedings of APRIM 2014, 12th Asia-Pacific Regional IAU Meeting, August 18 - 22, 2014, DCC, Daejeon, Korea, edited by Young Chol Minh and Hoil Kim)   30 ( 2 ) 731 - 733   2015.09

学童保育での「星企画」：その活動内容

富田晃彦

和歌山大学教育学部附属教育実践総合センター 紀要   ( 25 ) 33 - 41   2015.09

A co-operation with Serbia on Space and Astronomy Education: A report of activities in 2013

Akihiko Tomita, Dušan Radosavljević, Hiroaki Akiyama, Masachika A. Kijima, Masami Okyudo, Chiaki Yoshizumi, Naoko Sato, Tomomi Otani （Part： Lead author )

Bulletin of Institute for Education on Space ( 和歌山大学宇宙教育研究所 )  ( 3 ) 79 - 84   2014.03  [Refereed]

DOI

Kiso Supernova Survey (KISS): Survey strategy

Tomoki Morokuma, Nozomu Tominaga, Masaomi Tanaka, Kensho Mori, Emiko Matsumoto, Yuki Kikuchi, Takumi Shibata, Shigeyuki Sako, Tsutomu Aoki, Mamoru Doi, Naoto Kobayashi, Hiroyuki Maehara, Noriyuki Matsunaga, Hiroyuki Mito, Takashi Miyata, Yoshikazu Nakada, Takao Soyano, Ken'ichi Tarusawa, Satoshi Miyazaki, Fumiaki Nakata, Norio Okada, Yuki Sarugaku, Michael W. Richmond, Hiroshi Akitaya, Greg Aldering, Ko Arimatsu, Carlos Contreras, Takashi Horiuchi, Eric Y. Hsiao, Ryosuke Itoh, Ikuru Iwata, Koji S. Kawabata, Nobuyuki Kawai, Yutaro Kitagawa, Mitsuru Kokubo, Daisuke Kuroda, Paolo Mazzali, Toru Misawa, Yuki Moritani, Nidia Morrell, Rina Okamoto, Nikolay Pavlyuk, Mark M. Phillips, Elena Pian, Devendra Sahu, Yoshihiko Saito, Kei Sano, Maximilian D. Stritzinger, Yutaro Tachibana, Francesco Taddia, Katsutoshi Takaki, Ken Tateuchi, Akihiko Tomita, Dmitry Tsvetkov, Takahiro Ui, Nobuharu Ukita, Yuji Urata, Emma S. Walker, Taketoshi Yoshii

Publications of the Astronomical Society of Japan ( OXFORD UNIV PRESS )  66 ( 6 )   2014  [Refereed]

　View Summary

Article number: 114

DOI

Density waves and star formation in grand-design spirals

Bernabe Cedres, Jordi Cepa, Angel Bongiovanni, Hector Castaneda, Miguel Sanchez-Portal, Akihiko Tomita

ASTRONOMY & ASTROPHYSICS ( EDP SCIENCES S A )  560   2013.12  [Refereed]

　View Summary

Context. H II regions in the arms of spiral galaxies are indicators of recent star-forming processes. They may have been caused by the passage of the density wave or simply been created by other means near the arms. The study of these regions may give us clues to clarify the controversy about the existence of a triggering scenario, as proposed in the density-wave theory.
Aims. If the passage of the density wave contributes significantly to the formation of H II regions in the arms of grand-design spirals, we can find a relationship in their position relative to the arms.
Methods. Using Ha direct imaging, we characterize the H II regions from a sample of three grand-design galaxies: NGC 5457, NGC 628, and NGC 6946. Broad-band images in R and I were used to determine the position of the arms. The H II regions found to be associated with arms were selected for the study. The age and star formation rate of these H II regions was obtained using measurements on the Ha line. The distance between the current position of the selected H II regions and the position they would have if they had been created in the centre of the arm was calculated. A parameter, T, which measures whether a region was created in the arm or in the disc, was defined.
Results. With the help of the T parameter we determine that the majority of regions were formed some time after the passage of the density wave, and the regions are located behind the zone they should have occupied (in the direction of the rotation of the galaxy) had they been formed in the centre of the arm. Moreover, the relative efficiency of the star formation rate between arm and interarm was calculated for all the galaxies.
Conclusions. The large number of regions created after the passage of the arm may be explained by the effect of the density wave, which helps to create the star-forming regions after its passage. There is clear evidence of triggering for NGC 5457 and a co-rotation radius is proposed. A more modest triggering seems to exist for NGC 628, and insignificant evidence of triggering is found for NGC 6946.

DOI

宇宙観を伝えよう

富田晃彦

理科教室   56 ( 11 ) 37 - 42   2013.11  [Invited]

特別支援学校での宇宙のお話

富田晃彦

ユニバーサルデザイン天文教育研究会 集録     2013.01

Astronomy Outreach Activity at Nursery School

Akihiko Tomita （Part： Lead author )

Proceedings of the 11th Asian-Pacific Regional IAU Meeting (July 2011, Chiang Mai, Thailand), NARIT Conference Series   1   508 - 509   2013

Student education at "Cosmic Journal Club"

Tomita Akihiko

Bulletin of the Center for Educational Research and Training ( Wakayama University )  22   139 - 146   2012.09

DOI

IAU 天文学推進室（OAD）の発足：Astronomy for a Better World

富田晃彦, 臼田-佐藤功美子 （Part： Lead author )

天文教育 ( 日本天文教育普及研究会 )  24 ( 5 ) 69 - 73   2012.09

Two-dimensional metallicity distribution of the ionized gas in NGC 628 and NGC 6946

B. Cedres, J. Cepa, A. Bongiovanni, H. Castaneda, M. Sanchez-Portal, A. Tomita

ASTRONOMY & ASTROPHYSICS ( EDP SCIENCES S A )  545   A43   2012.09  [Refereed]

　View Summary

Aims. We present here two H II region catalogues with azimuthal resolution for the two grand design galaxies NGC 628 and NGC 6946. With the help of these catalogues, we study several properties of the star-forming processes occurring in spiral galaxies.
Methods. We obtained direct imaging in the narrow-band filters centred at H alpha, H beta, [O II]lambda 3727, and [O III]lambda lambda 4959, 5007 and their respective continua. After the calibration and correction of the data, we obtained for each H II region the de-reddened fluxes in the aforementioned lines, the size, the H alpha equivalent width, and, using two different empirical calibrations, the metallicity. Employing a method based on the Delaunay triangulation, a two-dimensional (2D) representation of the metallicity was obtained.
Results. Data for 209 H II regions of NGC 628 and 226 H II regions of NGC 6946 are obtained. The radial behaviours of the H alpha equivalent width, the excitation, and the oxygen abundance are derived. Two-dimensional representations of the metallicity and the excitation are calculated for the galaxies in the study. The two empirical calibrations of the metallicity are compared.
Conclusions. The behaviours of the extinction and the H alpha equivalent width are similar to those presented in the literature. The oxygen abundance gradients obtained in this study agree with previously published values. However, more regions were examined than in previous studies. We find a difference of about 0.6 dex between the two empirical calibrations employed. Finally, the 2D representations of the metallicity reveal high metallicity knots in NGC 628, and for NGC 6946 a high metallicity azimuthal structure is discovered. These high metallicity regions seem to be linked to the arms of the galaxies and are probably produced by an increase in the temperature of the ionizing clusters in the H II regions, which may be linked to variations in the initial mass functions of the galaxies between the arm and interarm regions.

DOI

2つの国際研究会EASE2011, APRIM2011に見える、天文教育とその国際協力における東・東南アジアでの動向

富田 晃彦

和歌山大学国際教育研究センター 年報   ( 8 ) 106 - 114   2012.03  [Refereed]

Photometric characteristics of CCD cameras equipped at astronomical observatory of Faculty of Education, Wakayama University

Tomita Akihiko

Bulletin of the Faculty of Education, Wakayama University. Natural science ( Wakayama University )  62   39 - 43   2012.02

DOI

保育園での「せいざものがたり」

富田晃彦, 河野明里

第25回天文教育研究会集録     163 - 165   2011.11

教育実習授業中に見られる「変化球」

富田 晃彦

和歌山大学教育学部附属教育実践総合センター 紀要   ( 21 ) 157 - 160   2011.09

Project SAZANKA: Multisite and Multifrequency Simultaneous SETI Observations in Japan

Shin-ya Narusawa, Mitsumi Fujishita, Hiroki Akisawa, Kenta Fujisawa, Yasuhide Fujita, Takahiro Fukuzumi, Hiromi Funakoshi, Hiroyuki Geshiro, Hideo Hara, Kenji Hashimoto, Tsutomu Hayamizu, Ryo Iizuka, Kazumasa Imai, Takeshi Inoue, Masayuki Kagami, Kazuhisa Kageyama, Takeshi Kamitamari, Masahiro Koishikawa, Shouta Maeno, Hidehiko Matsuo, Takashi Miyamoto, Masaki Morimoto, Hiroyuki Naito, Sumio Nakane, Takeshi Nakashima, Masami Okyudo, Takaaki Oribe, Takaaki Ozeki, Makoto Sakamoto, Yasuo Sano, Naoko Sato, Masayuki Tachikawa, Yoshimasa Tai, Setsuro Takahara, Yoshitaka Takahashi, Mikimasa Takeuchi, Naoto Tatsumi, Akihiko Tomita, Shinji Toyomasu, Naoki Toyoshima, Makoto Watanabe, Takeshi Yada, Ryoji Yamada, Michinari Yamamoto, Hideyo Yokotsuka

Communication with Extraterrestrial Intelligence, ed. Douglas A. Vakoch, State University of New York Press     109 - 124   2011.04

Astronomical Observatory of Faculty of Education, Wakayama University : Telescope and Instruments

Tomita Akihiko

Bulletin of the Faculty of Education, Wakayama University. Natural science ( Wakayama University )  61   17 - 22   2011.02

DOI

2009年7月22日の日食での気温変化

尾崎加織, 富田晃彦

学芸（和歌山大学教育学部学芸学会） ( 和歌山大学学芸学会 )  56 ( 56 ) 31 - 35   2010.03

ひかり保育園と Kaumana Keikiland のビデオメッセージ交換

富田晃彦, 岡田桂子, 井本トシミ, 臼田-佐藤功美子

和歌山大学国際教育研究センター年報   6   35 - 38   2010

和歌山での特別支援学校・院内学級への出張授業

富田晃彦 （Part： Lead author )

第23回天文教育研究会集録     116 - 119   2009.11

Report of a science cafe, Cafe Sakurasou

Tomita Akihiko, Okyudo Masami, Sato Naoko

Bulletin of the Faculty of Education, Wakayama University Educational science ( Wakayama University )  59   67 - 79   2009.02

DOI

和歌山大学での星空案内人®「星のソムリエ®」養成講座の開始

富田晃彦, 尾久土正己

和歌山大学教育学部附属教育実践総合センター紀要   ( 19 ) 99 - 104   2009

2005,2006年度観月会とその参加者層

富田晃彦, 尾久土正己, 矢動丸泰, 小澤友彦, 豊増伸治

和歌山大学生涯学習教育研究センター年報   ( 7 ) 9 - 13   2009

ふじと台でのサイエンスカフェの試行

富田 晃彦, 尾久土 正己, 佐藤 奈穂子

紀州経済史文化史研究所紀要 ( 和歌山大学紀州経済史文化史研究所 )  29 ( 29 ) 29 - 40   2008.12

A Visiting Class of Astronomy at Tachibana Supporting School

富田晃彦

和歌山大学教育学部附属教育実践総合センター紀要   18 ( 18 ) 107 - 112   2008

Development of a Small Radio Telescope for the Observations of the Neutral Hydrogen Emission Line and an Observing Lesson of the Milky Way at a High School

OKYUDO Masami, SATO Naoko, FUJISAWA Kenta, TOMITA Akihiko, ISHIZUKA Wataru, SATO Toshiyuki, SHIOKAWA Takayuki, CHIKATA Kensuke, YUKITANI Toshiyuki, HANDA Toshihiro

地学教育 ( 日本地学教育学会 )  60 ( 5 ) 171 - 178   2007.09  [Refereed]

大阪府南部と和歌山市の中学校・高等学校の天文分野学習に関する意識調査

富田晃彦, 尾久土正己, 三木誠 （Part： Lead author )

学芸（和歌山大学教育学部学芸学会）   ( 53 ) 71 - 79   2007.03

保育園児による「うちゅうのえ」

富田晃彦, 嶋田由美

和歌山大学教育学部附属教育実践総合センター紀要   ( 1781-84 )   2007

皆既日食の生中継を利用したサイエンスカフェの実施とその効果

尾久土正己, 藤垣元治, 矢治健太郎, 川橋裕, 富田晃彦, 渡辺政隆

和歌山大学国際教育研究センター年報   ( 3 ) 59 - 65   2007

プラネタリウムにおける日食の全天周生中継

尾久土正己, 荻原文恵, 小澤友彦, 吉住千亜紀, 富田晃彦, 山田宏之, 明井英太郎, 石川雅一, 山本文治, 中山雅哉, 半田利弘

地学教育   60 ( 3 ) 99 - 107   2007  [Refereed]

出張授業による学習意欲向上効果 — 中学校 1 年生に対する天文分野の単発的授業での例 —

富田晃彦, 川崎由紀子

和歌山大学教育学部紀要 (自然科学)   57   29 - 32   2007

教育実践論文 金星太陽面通過のインターネット中継とその教材化

荻原 文恵, 尾久土 正己, 富田 晃彦

地学教育 ( 日本地学教育学会 )  59 ( 6 ) 201 - 212   2006.11  [Refereed]

GRB 050124: KISO optical limit

Tomita, A, Nishiura, S, Urata, Y, Huang, K.-Y

GRB Coordinates Network, Circular   ( 4575 ) 1   2006

Comparison of the H alpha equivalent width of HII regions in a flocculent and a grand-design galaxy: Possible evidence for initial mass function variations

B Cerdres, J Cepa, A Tomita

ASTROPHYSICAL JOURNAL ( UNIV CHICAGO PRESS )  634 ( 2 ) 1043 - 1055   2005.12  [Refereed]

　View Summary

We present here a study of the H alpha equivalent widths of the flocculent galaxy NGC 4395 and the grand-design galaxy NGC 5457. A difference between the mean values of the H alpha equivalent widths for the two galaxies has been found. Several hypotheses are presented in order to explain this difference: differences in age, metallicity, star formation rate, photon leakage, and initial mass function. Various tests and Monte Carlo models are used to find out the most probable cause of this difference. The results show that the possible cause for the difference could be a variation in the initial mass function. This difference is such that it seems to favor a fraction of more massive stars in the grand-design galaxy when compared with the flocculent galaxy. This could be due to a change of the environmental conditions due to a density wave.

DOI

彼方の銀河世界: 銀河 (全宇宙鉄道路線ガイド 第11回)

富田晃彦

パリティ ( 丸善 )  20 ( 3 ) 66 - 73   2005

Promotion of Collaborations via the Internet on Intercultural Education and Students' Independent Cross-cultural Activities : Projects and Issues

Fujinaga Hiroshi, Endo Fubito, Iwata Hideaki, Hatcho Naoyuki, Takeda Katsuaki, Nagatomo Ayako, Tomita Akihiko, Nonaka Yoichi

The Wakayama economic review ( Wakayama University )  320 ( 320 ) 1 - 22   2004.07

DOI

和歌山大学と地域公開天文台・科学館の連携の紹介とその評価

富田 晃彦, 尾久土 正己, 矢治 健太郎, 曽我 真人

天文月報 ( 日本天文学会 )  97 ( 2 ) 88 - 95   2004.01

インターネット・イベントを利用した自主演習 — 南極皆既日食中継のWeb コンテンツの制作 —

尾久土正己, 富田晃彦

和歌山大学教育学部附属教育実践総合センター 紀要   ( 14 ) 45 - 48   2004

郷土の星の伝承者

富田晃彦

和歌山大学紀州経済史文化史研究所紀要   24   17 - 47   2004

A Study of Science Education Using Planetarium

佐々木順子, 富田晃彦

和歌山大学教育学部附属教育実践総合センター紀要   14 ( 14 ) 55 - 60   2004

カメラ付き携帯電話を利用した天文教育

竹中敦史, 富田晃彦

和歌山大学教育学部附属教育実践総合センター 紀要   ( 14 ) 49 - 54   2004

The Virgo high-resolution CO survey: I. CO atlas

Y Sofue, J Koda, H Nakanishi, S Onodera, K Kohno, A Tomita, SK Okumura

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN ( OXFORD UNIV PRESS )  55 ( 1 ) 17 - 58   2003.02  [Refereed]

　View Summary

We present the results of the Virgo high-resolution CO survey (ViCS) obtained with the Nobeyama Millimeter-wave Array (NMA). This survey was made during the course of a long-term project at Nobeyama from 1999 December through 2002 April. The objects were selected from Virgo cluster members, while considering the CO richness from the single-dish flux, mild inclination, and a lack of strong tidal perturbations. The central V regions similar to 4.7 kpc of 15 spiral galaxies were observed with resolutions of 2"-5" and 10-20 kms(-1), and sensitivities of 20 mJy beam(-1) for a 10 kms(-1) channel. The objects lie at the same distance of the Virgo cluster (16.1 Mpc), which is advantageous for comparisons among individual galaxies. We describe the details of observations and data reduction, and present an atlas of integrated CO intensity maps, velocity fields and position-velocity diagrams along the major axes. The molecular gas morphology in the Virgo galaxies shows a wealth of variety, not specifically depending on the Hubble types. Several galaxies show a strong concentration of gas in the central few kpc region, where the CO morphology shows either a "single-peak" or a "twin-peaks". The morphology of more extended CO components can be classified into "arm-type", "bar-type", and "amorphous-type".

DOI

Erratum: The Virgo High-Resolution CO Survey: I. CO Atlas (Publication of the Astronomical Society of Japan (2003) 55 (17-58))

Yoshiaki Sofue, Jin Koda, Hiroyuki Nakanishi, Sachiko Onodera, Kotaro Kohno, Akihiko Tomita, Sachiko K. Okumura

Publications of the Astronomical Society of Japan ( Oxford University Press )  55 ( 6 ) 1189 - 1190   2003  [Refereed]

DOI

The Virgo high-resolution CO-line survey

Y Sofue, J Koda, H Nakanishi, S Onodera, K Kohno, A Tomita, SK Okumura

PROCEEDINGS OF THE IAU 8TH ASIAN-PACIFIC REGIONAL MEETING, VOL I ( ASTRONOMICAL SOC PACIFIC )  289   129 - 134   2003  [Refereed]

　View Summary

We present the results of the Virgo high-resolution CO survey (VCOS) obtained with the Nobeyama Millimeter-wave Array at highangular and spectral-resolutions in the (CO)-C-12 (J = 1 - 0) line emission for 15 Virgo CO-rich spirals. The central CO distributions can be classified into the "central/single-peak type", which is a majority, and "twinpeaks". We derived exact rotation curves by applying a new iteration method to position-velocity diagrams, which show generally a steep central rise, indicating central massive cores.

Properties of spiral-peculiar type of Kiso ultraviolet-excess galaxies

A Tomita, H Maehara

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN ( OXFORD UNIV PRESS )  54 ( 5 ) 661 - 682   2002.10  [Refereed]

　View Summary

We investigated the optical spectroscopic properties of 44 Kiso Ultraviolet-excess Galaxies (KUG), which is one of the most well-known catalogs of blue galaxies. All of our sample galaxies belong to the spiral-peculiar (Sp) type, the morphological class of spiral galaxy with a peculiar bar and/or a nucleus in KUGs. Since the Sp type is considered to be the most peculiar group among KUGs, and about 45% of the KUGs have the Sp type, a detailed study of the Sp type is crucial to understand the characteristics of the KUG. The sample galaxies have luminosities in the B-band of about 10(8) to less than 10(10) in solar unit, and a median physical size of 13 kpc. From the nuclear spectra, we determined line excitation sources in 39 galaxies. Among them, we detected four AGNs reliably: two Seyfert 1s, one Seyfert 2, and one LINER. Other sample galaxies show moderately star-forming activity. For this category of ordinary KUG group, the mode of the Ha equivalent width at the nuclear region is a bin of 40 to 60 Angstrom. Three galaxies have extreme starburst nuclei with an Ha equivalent width of more than 200 Angstrom. The internal extinction of A(V) is about 0.8 mag, which suggests that the star-forming nuclei are not heavily enshrouded by dust.

DOI

国際化時代の地域天体観望会：大阪日本語教育センターでの実践例

富田晃彦, 上之山幸代, 鷺坂奏絵 （Part： Lead author )

和歌山大学教育学部紀要, 教育科学   70   83 - 88   2002.02

Star Formation History of Irregular Galaxies through Analysis of Optical Spectra

Tomita, A, Yoshikawa, K, Takeuchi, T.T, Hirashita, H

The Proceedings of the IAU 8th Asian-Pacific Regional Meeting, Volume II, ed. S. Ikeuchi, J. Hearnshaw, and T. Hanawa (The Astronomical Society of Japan, Tokyo)     301 - 302   2002

早期型銀河の中心部ガス系

富田晃彦

天文月報   95 ( 6 ) 278 - 281   2002

地上に残った超新星の痕跡 (翻訳)

富田晃彦

パリティ   18 ( 3 ) 39 - 42   2002

The UV (GALEX) and FIR (ASTRO-F) All Sky Surveys: the Measure of the Dust Extinction in the Local Universe

Buat, V, Takeuchi, T, Boselli, A, Burgarella, D, Hirashita, H, Tomita, A, Shibai, H, Milliard, B, Donas, J, Yoshikawa, K, Inoue, A, Tajiri, Y

The Proceedings of the IAU 8th Asian-Pacific Regional Meeting, Volume II, ed. S. Ikeuchi, J. Hearnshaw, and T. Hanawa (The Astronomical Society of Japan, Tokyo)     65 - 66   2002

GRB 020317: KISO optical observations

Tomita, A, Takeuchi, T.T, Furukawa, S, Nishibata, K, Yamamoto, M, Urata, Y, Nishiura, S, Nakata, Y, Miyata, T. Aoki, T, Soyano, T, Tarusawa, K, Mito, H, Yoshida, A, Kawai, N, Tamagawa, T

GRB Coordinates Network, Circular   ( 1281 ) 1   2002

Spectroscopic observations of the star formation activities in the central regions of early-type spiral galaxies

T Usui, M Saito, A Tomita

ASTRONOMICAL JOURNAL ( UNIV CHICAGO PRESS )  121 ( 5 ) 2483 - 2498   2001.05  [Refereed]

　View Summary

We study the characteristics of central star-forming regions of early-type spiral galaxies by optical spectroscopic observations. The sample consists of 13 galaxies which have ratios of far-infrared (FIR) to optical B-band luminosity, log (L-FIR/L-B), larger than the average of this type, -0.5. Strong line emissions are detected around the nucleus, and the line ratios of most regions are H II region-like, except for a few shocked regions. There is no low-ionization nuclear emission-line region (LINER). The [N II] and [S II] lines are somewhat enhanced, compared to the disk H II regions, but the enhancements cannot be attributed to hidden active galactic nuclei (AGNs) and the shock excitation. The median extinction derived from the H alpha /H beta intensity ratio is 1.0 mag in A(V), and the median SFR of our sample galaxies, corrected for extinction, is estimated to be 2 M. yr(-1). Both values are comparable to those of late-type spiral galaxies. We find a correlation that the radii of the central star-forming regions tend to become larger with the turn-over radii of the rotation curves.

DOI

The central gas systems of early-type galaxies traced by dust features, based on the Hubble Space Telescope WFPC2 archival images

A Tomita, K Aoki, M Watanabe, T Takata, S Ichikawa （Part： Lead author )

The Astronomical Journal ( UNIV CHICAGO PRESS )  120 ( 1 ) 123 - 130   2000.07  [Refereed]

　View Summary

We investigated the central gas systems of E/SO galaxies by making use of the WFPC2 images in the Hubble Space Telescope archive. We searched for gas systems that were traced by the dust with a new method of making color excess images in F555W-F814W (V-I). Of 25 sample galaxies, we detected gas systems in 14 galaxies. The dust was newly detected in two galaxies that were thought to contain no dust based on single-band, prerefurbishment data. The full extents of the gas systems are 0.1-3.5 kpc, and the masses of the gas, log M-gas [M-.] are 4.2-7.2. The active galactic nucleus (AGN) activity is well correlated with the existence of the; gas systems. None of galaxies without the gas systems show AGN activity. On the other hand, some galaxies with gas systems show AGN activity; optical AGN activities are shown in five of 11 galaxies in which AGNs are optically studied, and radio activities are shown in six of 14 galaxies. This shows that the AGN activity is driven with the gas system.

Interstellar-cloud formation in the extended envelopes of blue compact dwarf galaxies

Mamoru Saito, Hideyuki Kamaya, Akihiko Tomita

Publications of the Astronomical Society of Japan ( Astronomical Society of Japan )  52 ( 5 ) 821 - 827   2000  [Refereed]

　View Summary

Blue compact dwarf galaxies (BCDs) have an interesting feature in their central region where stars are actively forming. In this paper, we show that shock waves produced by the starbursts there are able to trigger self-gravitating interstellar clouds in extended envelopes, which are often observed in typical BCDs. The criterion adopted for the formation of interstellar clouds is very simple, that is, ρ &gt
2Γρ̄/3. Here, ρ is the gas density of the shocked layer, ρ̄ is a mean density including the dark matter, and Γ is a numerical factor between 0.5 and 1.0, depending on the mass distribution of the galaxy. Hence, we suggest that the infalling of the clouds onto the central regions causes subsequent starbursts after ∼ 0.1 Gyr of the event, and that the episodic starbursts continue during sub-Gyr.

DOI

InterStellar-Cloud Formation in the Extended Envelopes of Blue Compact Dwarf Galaxies

Saito, M, Kamaya, H, Tomita, A

Mapping the Hidden Universe: The Universe behind the Milky Way - The Universe in HI, ASP Conference Proceedings eds. Renee C. Kraan-Korteweg, Patricia A. Henning, and Heinz Andernach (The Astronomical Society of the Pacific)   218   305   2000

Central kinematics and rotation curve of the Sb galaxy NGC 4527 in CO, H alpha, and [NII] lines

Y Sofue, A Tomita, M Honma, Y Tutui

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN ( OXFORD UNIV PRESS )  51 ( 5 ) 737 - 743   1999.10  [Refereed]

　View Summary

We have obtained interferometer observations of the central region of the Sb galaxy NGC 4527 in the CO (J = 1-0) line emission using the Nobeyama Millimeter Array. We also obtained optical (H alpha, [N II]) spectroscopy using the Okayama 188-cm reflector along the major axis. The kinematical structure and the distribution of H II regions show symmetry around the nucleus, while the distribution of molecular gas is asymmetric. The molecular-gas mass shares only 10% of the dynamical mass in the central 1 kpc radius region. Using position-velocity diagrams, we have derived a center-to-disk rotation curve. It rises steeply in the central region, attaining a maximum of about 250 km s(-1) at 400 pc radius, and then decreases to a minimum at 2 kpc radius, followed by a disk and outer flat part. The rotation curve may provide us with the most similar case to that of the Milky Way Galaxy.

DOI

Central rotation curves of spiral galaxies

Y Sofue, Y Tutui, M Honma, A Tomita, T Takamiya, J Koda, Y Takeda

ASTROPHYSICAL JOURNAL ( UNIV CHICAGO PRESS )  523 ( 1 ) 136 - 146   1999.09  [Refereed]

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We present high-resolution central-to-outer rotation curves for Sb, SBb, Sc, and SBc galaxies. We discuss their general characteristics, particularly their central behavior, as well as dependencies on morphological types, activity, and peculiarity. The rotation curves generally show a steep nuclear rise and high-velocity central rotation, followed by a broad maximum in the disk and then a flat rotation due to the massive halo. Since the central high velocity and steep rise are common to all massive galaxies, they cannot be due to noncircular motions. Disk rotation curves of barred galaxies show larger dispersion than those of normal galaxies, probably because of noncircular motions. Interacting galaxies often show perturbed outer rotation curves, while their central rotation shows no particular peculiarity. In addition, central activities, such as starbursts and active galactic nuclei, appear to show no particular correlation with the property of rotation curves. This would suggest that the central activities are triggered by a more local effect: than the global dynamical property.

Optical and CO radio observations of poor cluster Zwicky 1615.8+3505

A Tomita, H Maekara, TT Takeuchi, K Nakanishi, M Honma, Y Tutui, Y Sofue

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN ( OXFORD UNIV PRESS )  51 ( 3 ) 285 - 300   1999.06  [Refereed]

　View Summary

The cluster Zwicky 1615.8+3505 is considered to be a dynamically young poor cluster. To investigate the morphology and star-formation activity of galaxies under the environment of a dynamically young poor cluster, we have performed V, R, and I surface photometry, optical low-resolution spectroscopy, and (CO)-C-12 (J = 1-0) line observations for member galaxies. Our data show that more than 90% of the observed galaxies show regular morphologies and no star-formation activities, indicating that the environment does not affect these galaxy properties. Among sixteen galaxies observed, only NGC 6104 shows a significant star-formation activity, and shows a distorted morphology, indicating a tidal interaction. This galaxy contains double knots, and only one knot possesses Seyfert activity, though the sizes and luminosities are similar to each other; we also discuss this feature.

DOI

Photometric properties of Kiso ultraviolet-excess galaxies in the Lynx-Ursa Major region

TT Takeuchi, A Tomita, K Nakanishi, TT Ishii, Iwata, I, M Saito

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES ( UNIV CHICAGO PRESS )  121 ( 2 ) 445 - 472   1999.04  [Refereed]

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We have performed a systematic study of several regions in the sky where the number of galaxies exhibiting star formation (SF) activity is greater than average. We used Kiso ultraviolet-excess galaxies (KUGs) as our SE-enhanced sample. By statistically comparing the KUG and non-RUG distributions, we discovered four RUG-rich regions with sizes of similar to 10 degrees x 10 degrees. One of these regions corresponds spatially to a filament of length similar to 60 h(-1) Mpc in the Lynx-Ursa Major region (alpha similar to 9(h)-10(h), delta similar to 42 degrees-48 degrees). We call this "the Lynx-Ursa Major (LUM) filament." We obtained V(RI)(C) surface photometry of 11 of the KUGs in the LUM filament and used these to investigate the integrated colors, the distribution of SF regions, the morphologies, and the local environments. We found that these KUGs consist of distorted spiral galaxies and compact galaxies with blue colors. Their star formation occurs in the entire disk and is not confined to just the central regions. The colors of the SF regions imply that active star formation in the spiral galaxies occurred 10(7-8) yr ago, while that in the compact objects occurred 10(6-7) yr ago. Though the photometric characteristics of these KUGs are similar to those of-interacting galaxies or mergers, most of these KUGs do not show direct evidence of merger processes.

DOI

Vertical motion of molecular and ionized gas in nearby face-on galaxies

S Sakamoto, A Tomita

NEW PERSPECTIVES ON THE INTERSTELLAR MEDIUM ( ASTRONOMICAL SOC PACIFIC )  168   283 - 286   1999

　View Summary

We have made high-resolution (CO)-C-12 J=1-0 images of NGC 628 (i = 6 degrees, D = 10 Mpc) to study the vertical motions of molecular gas, and high-dispersion scanning-slit spectroscopy of H alpha emission in NGC 628 and NGC 3938 (i = 10 degrees, D = 10 Mpc) to trace the vertical motions of ionieed gas. Supplemental images in narrow-band H alpha and J- and K' bands were also obtained.
The vertical velocity dispersion of molecular gas is 6.4 +/- 1.5 km s(-1) throughout the inner (0.5-6 kpc) disk without any systematic radial variation. The vertical velocity dispersion of molecular gas at 5 kpc from the center is smaller than that of atomic gas at the same distance by a factor of similar to 1.5 This difference naturally explains the fact that molecular disks in spiral galaxies are generally thinner than atomic gas disks by a factor of similar to 1.5 Although there is a significant point-to-point variation of the velocity dispersion, no simple correlations with CO brightness (gas surface density), K'-band brightness (stellar gravitational potential), or Her brightness (star-formation activity) are observed. There is no high-velocity (\Delta v(perpendicular to)\ &gt; 30 km s(-1)) molecular gas detected with our 5 sigma sensitivity of similar to 5 X 10(5) M. per 680 pc beam. This suggests that disk-halo connection of ISM in the form of molecular gas is a rare phenomenon.
In contrast, high-dispersion H alpha spectroscopy of NGC 628 and NGC 3938 revealed that there are hints of peculiar vertical motion (\Delta v(perpendicular to)\ &gt; 30 km s(-1)) of ionized gas probably related with disk-halo connection of the ISM. The regions with peculiar motions are associated with bright HII regions and may originate from expanding motions associated with massive star formation activity.

Star Formation Activity Depending on Size of Galaxy

Akihiko Tomita, Tsutomu T. Takeuchi, Hiroyuki Hirashita

Star Formation 1999, ed. Taishi Nakamoto (Nobeyama Radio Observatory)     50 - 51   1999

Photometric observations of star formation activity in early-type spiral galaxies

T Usui, M Saito, A Tomita

ASTRONOMICAL JOURNAL ( UNIV CHICAGO PRESS )  116 ( 5 ) 2166 - 2176   1998.11  [Refereed]

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We observationally study the current star formation activities of early-type spiral galaxies. We construct a complete sample of 15 early-type spiral galaxies having ratios of far-infrared (FIR) to optical B-band luminosity, log (L-FIR/L-B), larger than average for this type and present CCD imaging of the R and H alpha bands. The equivalent widths of H alpha emission increase with increasing L-FIR/L-B indicating that log (L-FIR/L-B) can be an indicator of star formation for such early-type spiral galaxies with star formation activities higher than average. For all of the observed early-type spiral galaxies, the extended H II regions exist at the central regions with some asymmetric features. H alpha emission is more concentrated to the galactic center than the R-band light, and the degree of the concentration increases with the star formation activity. We also analyze the relation between the star formation activities and the existence of companion galaxies in the sample galaxies and other bright early-type spiral galaxies. No correlation is found; this suggests that the interaction is not responsible for all of the star formation activities of early-type spiral galaxies.

Nuclear-to-disk rotation curves of galaxies in the H alpha and [N II] emission lines

Y Sofue, A Tomita, Y Tutui, M Honma, Y Takeda

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN ( OXFORD UNIV PRESS )  50 ( 5 ) 427 - 463   1998.10  [Refereed]

　View Summary

We have obtained optical CCD spectroscopy along the major axes of 22 nearby spiral galaxies of Sb and Sc types in order to analyze their rotation curves. By subtracting the stellar continuum emission, we have obtained position-velocity (PV) diagrams of the H alpha and [N II] lines. We point out that the H alpha line is often superposed by a broad stellar absorption feature (Balmer wing) in the nuclear regions, and, therefore, the [N II] line is a better tracer of kinematics in the central few hundred parsec regions. By applying the envelope-tracing technique to the H alpha and [N II] PV diagrams, we have derived nucleus-to-disk rotation curves of the observed galaxies. The rotation curves rise steeply within the central few hundred parsecs, indicating a rapidly rotating nuclear disk and mass concentration near the nucleus.

DOI

Hot velocity fields of H II regions in nearby dwarf irregular galaxies

A Tomita, K Ohta, K Nakanishi, TT Takeuchi, M Saito （Part： Lead author )

ASTRONOMICAL JOURNAL ( UNIV CHICAGO PRESS )  116 ( 1 ) 131 - 145   1998.07  [Refereed]

　View Summary

We present H alpha velocity fields of 13 giant H II regions in four nearby dwarf irregular galaxies: NGC 2366, Holmberg II, IC 2574, and WLM (the Wolf-Lundmark-Melotte system). We classify the velocity features, as well as the morphologies, of the H II regions. The H alpha velocity features are divided into three categories; three H II regions show chaotic features with a typical scale of variation of a few hundred parsecs in size and a few times 10 km s(-1) in velocity, one region exhibits an expanding-bubble feature, and the remaining nine have calm velocity fields. There is a correlation between the H alpha velocity features and the morphology of the H II regions. We measured the bulk motion of the H II regions relative to the ambient H I velocity for the II Ir regions with calm velocity fields and found a typical velocity difference of about 5 km s(-1). We discuss a model for the origin of star-forming regions based on the presence of the velocity difference between H alpha and H I gas, as well as the H I characteristics.

Nuclear rise of rotation curves of galaxies

Y Sofue, Y Tutui, M Honma, A Tomita

CENTRAL REGIONS OF THE GALAXY AND GALAXIES ( SPRINGER )  184   51 - 52   1998

Nuclear rotation curves of galaxies in the co-line emission

Y Sofue, Y Tutui, M Honma, A Tomita

ASTRONOMICAL JOURNAL ( AMER INST PHYSICS )  114 ( 6 ) 2428 - 2436   1997.12  [Refereed]

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We have obtained high-resolution position-velocity (PV) diagrams along the major axes of the central regions of nearby galaxies in the CO-line emission using the Nobeyama 45 m telescope and the Millimeter Array. Nuclear rotation curves for 14 galaxies have been derived based on the PV diagrams using the envelope-tracing method. The nuclear rotation curves for most of the galaxies show a steep rise within a few hundred pc, which indicates a high-density concentration of mass. (C) 1997 American Astronomical Society. [S0004-6256(97)02512-0].

Characteristics of Kiso Ultraviolet Excess Galaxies

A Tomita, TT Takeuchi, T Usui, M Saito （Part： Lead author )

ASTRONOMICAL JOURNAL ( AMER INST PHYSICS )  114 ( 5 ) 1758 - 1770   1997.11  [Refereed]

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We examined the general characteristics of the Kiso Ultraviolet Excess Galaxies (KUGs). We present for the first time the quantitative expressions for the criteria of the KUGs; the boundary color separating the KUGs from the non-KUGs is (B - V)(T) = 0.74 and the KUG degrees of UV strength are found to correlate with the mean (B - V)(T) colors. We investigate the nature of the KUGs, a sample of blue galaxy population, and show that (1) about a half of the KUGs are spiral galaxies with Sb to Scd, (2) the KUGs are biased to late-type galaxies and include early-type galaxies with young star populations, and (3) the KUGs are preferably found among less luminous galaxies with L-B&lt;10(10)L.. The KUGs also contain the post-starburst galaxies, many of which are found among the blue galaxy population at intermediate redshifts. The analysis of the far-infrared data shows that a typical present-to-past star formation rate for a KUG is 0.4. (C) 1997 American Astronomical Society.

Catalog of Galaxies and Galaxy Candidates behind the Milky Way Vol.3 : Galactic Longitude 8 degree to 43 degree, Galactic Latitude -17 degree to 17 degree

Adel T. Roman, K. Nakanishi, A. Tomita, M. Saito

Contributions from the Department of Astronomy Kyoto University   ( 570 )   1997

A search for galaxies behind the Milky Way at Aquila and Sagittarius

AT Roman, K Nakanishi, A Tomita, M Saito

Publications of the Astronomical Society of Japan ( OXFORD UNIV PRESS )  48 ( 5 ) 679 - 690   1996.10  [Refereed]

　View Summary

We searched for galaxies using Schmidt atlases in a Milky Way region of about 800 square degrees around l similar or equal to 8 degrees to 43 degrees and b similar or equal to -17 degrees to 17 degrees. The surveyed region is located between the northern Local void and the Ophiuchus void. We detected about 5300 galaxy candidates, which have galaxy-like images with sizes larger than 0'.1. Of these, only 30 have been given in galaxy catalogs and another 74 are associated with IRAS point sources containing 18 IRAS galaxies with known redshifts. We made a catalog of detected objects in which the position in (alpha, delta) and (l, b), size, and features of image and multiplicity are given. The sky distribution of detected objects shows the presence of two clusters of galaxies and a group of nearby galaxies located around l = 33 degrees, b = -15 degrees with cz = 1500 km s(-1).

DOI

Distribution of blue galaxies in a merging cluster of galaxies Abell 168

A Tomita, FE Nakamura, T Takata, K Nakanishi, M Takeuchi, K Ohta, T Yamada （Part： Lead author )

The Astronomical Journal ( IOP PUBLISHING LTD )  111 ( 1 ) 42 - 52   1996.01  [Refereed]

　View Summary

The fraction of-star-forming galaxies in rich clusters of galaxies increases rapidly with the redshift. This is interpreted as the result of a rapid evolution of cluster galaxies, though its mechanism is not yet dear. One hypothesis is that if galaxies run into the dense intracluster medium (ICM) regions, starbursts can be induced due to the compression of molecular clouds in the galaxies by a raised &apos;&apos;external&apos;&apos; ICM pressure. In a merging cluster, there would be dense ICM regions and some galaxies may experience a rapid increase of external pressure. Thus, if the mechanism works, starbursts would occur in such galaxies. Such a situation is considered to be realized in Coma cluster, and galaxies showing a recent starburst have a characteristic spatial distribution; they populate an elongated region between two subclusters. We examined the above hypothesis by measuring the spatial distribution of blue galaxies, regarded as star-forming galaxies in Abell 168 to check whether a case Like Coma is realized in this recently merging cluster. However, we could not find an enhanced blue-galaxy distribution between two subclusters. We discuss the causes of our result, including the possibilities of surviving the hypothesis. (C) 1996 American Astronomical Society.

DOI

Post Starburst Nucleus of NGC 5195

Toru Yamada, Akihiko Tomita

Ground-Based Astronomy in Asia, 3rd East-Asian Meeting on Astronomy, ed. N. Kaifu (NAOJ, Tokyo)     268 - 271   1996

A variation in the present star formation activity of spiral galaxies

Akihiko Tomita, Yoshio Tomita, Mamoru Saito

Publications of the Astronomical Society of Japan ( Astronomical Society of Japan )  48 ( 2 ) 285 - 303   1996

　View Summary

The star formation rate in spiral galaxies is considered to be continuously decreasing with time on a time scale of 109 yr. The present star formation activity, on the other hand, occurs in molecular clouds with a time scale of 107 yr, and shows various degrees among galaxies. We have made a new data set of 1681 nearby spiral galaxies from available databases, and have studied the statistics of the present star formation activity. We analyzed the far-infrared and optical B-band surface brightnesses of the H II regions and the non-H II regions in M31, and have shown that the far-infrared-to-optical B-band flux ratio (fFIR/fB) is a useful indicator of the present star formation activity of spiral galaxies. For the sample galaxies, we made a distribution diagram of log(fFIR/fB) versus log LB for each morphological type. The distribution of fFIR/fB has a dispersion of one to two orders of magnitude, even within the same morphological type of galaxies, implying that the star formation activities of spiral galaxies change discontinuously within a short time scale. After analyzing the log(fFIR/fB) versus log LB correlation, we suggest that the most active star formation in galaxies does not continue longer than 108 yr. We also constructed a universal histogram of log(fFIR/fB) for each morphological type. The earlier-type spirals tend to show a larger variation in the present star formation activity. We discuss the correlation between the present star formation activity and the structures and environments of galaxies. We suggest that a short-term variation occurs primarily due to internal processes which may change with the morphological type of galaxies.

DOI

A variation in the present star formation activity of spiral galaxies

Akihiko Tomita, Yoshio Tomita, Mamoru Saito （Part： Lead author )

Publications of the Astronomical Society of Japan ( Astronomical Society of Japan )  48 ( 2 ) 285 - 303   1996  [Refereed]

　View Summary

The star formation rate in spiral galaxies is considered to be continuously decreasing with time on a time scale of 109 yr. The present star formation activity, on the other hand, occurs in molecular clouds with a time scale of 107 yr, and shows various degrees among galaxies. We have made a new data set of 1681 nearby spiral galaxies from available databases, and have studied the statistics of the present star formation activity. We analyzed the far-infrared and optical B-band surface brightnesses of the H II regions and the non-H II regions in M31, and have shown that the far-infrared-to-optical B-band flux ratio (fFIR/fB) is a useful indicator of the present star formation activity of spiral galaxies. For the sample galaxies, we made a distribution diagram of log(fFIR/fB) versus log LB for each morphological type. The distribution of fFIR/fB has a dispersion of one to two orders of magnitude, even within the same morphological type of galaxies, implying that the star formation activities of spiral galaxies change discontinuously within a short time scale. After analyzing the log(fFIR/fB) versus log LB correlation, we suggest that the most active star formation in galaxies does not continue longer than 108 yr. We also constructed a universal histogram of log(fFIR/fB) for each morphological type. The earlier-type spirals tend to show a larger variation in the present star formation activity. We discuss the correlation between the present star formation activity and the structures and environments of galaxies. We suggest that a short-term variation occurs primarily due to internal processes which may change with the morphological type of galaxies.

DOI

A Nuclear Ring in the Sa(r!) Galaxy NGC7742

K. Wakamatsu, M. Hamabe, M.T. Nishida, A. Tomita

The Astronomical Society of the Pacific Conference Series(Barred Galaxies, IAU Colloquium No.157)   91   83 - 85   1996

CO OBSERVATIONS OF THE HIGH-REDSHIFT RADIO GALAXY 53W002

T YAMADA, K OHTA, A TOMITA, T TAKATA

ASTRONOMICAL JOURNAL ( AMER INST PHYSICS )  110 ( 4 ) 1564 - 1572   1995.10  [Refereed]

　View Summary

We observed a high redshift radio galaxy 53W002 at z=2.390 with the Nobeyama 45 m telescope aiming at a detection of a redshifted (CO)-C-12 (J=1-0) emission line. The galaxy was discovered in the Leiden Berkeley Deep Survey and is known to have a blue SED and is a candidate for a genuinely young galaxy. We detected a weak (similar to 5 mJy) emission-line feature at z=2.392; the feature was significant in our November 1993 observations and marginally confirmed in the follow-up observations held in December 1993 and February 1994. If the detected emission-line feature is really a redshifted CO emission line associated with 53W002, its luminosity is 1.2x10(11) h(-2) K km s(-1) pc(2) (q(0)=0.5), or, H(H-2)similar to 5 X 10(11) h(-2) H-circle dot, adopting the galactic CO-to-H-2 conversion factor. (C) 1995 American Astronomical Society.

DOI

NGC-7217 - A SPHEROID-DOMINATED, EARLY-TYPE RESONANCE RING SPIRAL GALAXY

R BUTA, W VANDRIEL, J BRAINE, F COMBES, K WAKAMATSU, Y SOFUE, A TOMITA

ASTROPHYSICAL JOURNAL ( UNIV CHICAGO PRESS )  450 ( 2 ) 593 - 615   1995.09  [Refereed]

　View Summary

NGC 7217 is a well-known northern spiral galaxy which is characterized by flocculent spiral structure and a series of three optical ringlike zones: a nuclear ring 21 '' in diameter, a weak inner ring 63 '' in diameter, and a striking outer ring 2.'6 in diameter. The rings all have nearly the same shape and position angle in projection. The appearance of the galaxy suggests that it may be more axisymmetric than the typical spiral galaxy, since there is little evidence for the presence of a bar, oval, or stellar density wave. This makes the origin of the ring features uncertain. In an effort to understand this kind of ringed galaxy, which is by no means typical, we have obtained multicolor CCD BVRI images, accurate surface photometry, mappings of the CO and HI gas distributions, and rotational velocities from H alpha and HI spectral line data.
Our deep surface photometry has revealed an important feature of NGC 7217 that was missed in previous studies: The region occupied by the rings of the galaxy is surrounded-by an extensive, nearly circular luminous halo. This halo cannot be merely an extension of the disk component because it is much rounder than the inner regions. Instead, we believe the light represents either the outer regions of the bulge or a separate stellar halo component. We are able to successfully model the luminosity profile in terms of an r(1/4) ''spheroid'' and an exponential disk with a spheroid-to-total disk (including rings) luminosity ratio of 2.3-2.4. This makes NGC 7217 one of the most spheroid-dominated spirals known, and the finding has important implications for the recent discovery by Merrifield and Kuijken of a significant population of counter-rotating stars in the galaxy. Although the spiral structure of NGC 7217 is flocculent in blue light, there is a definite two-armed stellar spiral in the region of the outer ring. This ring includes about 4.4% of the total blue luminosity and is the locus of most of the recent star formation in the galaxy.
The ring is also where we find the HI gas to be concentrated. The galaxy is very gas poor (M(HI) = L(B)(0) = 0.024 M.IL.,(B)) for its morphological type. The HI rotational velocities agree well with published and our new H alpha-values.
Fourier analysis reveals a very weak possible oval distortion in the stellar mass distribution. Using the I-band light distribution to define the potential, we carried out simulations of gas streaming with no self-gravity. A model with a bulge-to-disk mass ratio of 2.4 reproduces the observed optical ring morphology very well. This suggests to us that in spite of the extreme weakness of the observed nonaxisymmetry of this galaxy, this nonaxisymmetry is still sufficient to torque the gas into the usual resonance rings identified in other, more obviously barred galaxies.
An additional noteworthy feature that we have identified in a B-I color index map is a symmetric, nuclear dust ring 17 '' in angular diameter. Other dust lanes are seen mainly on the near side of the galaxy.

POSSIBLE DETECTION OF A CO EMISSION-LINE FROM A QUASAR AT Z=2.88

T YAMADA, K AOKI, A TOMITA, T TAKATA, K OHTA, M YOSHIDA

ASTROPHYSICAL JOURNAL ( UNIV CHICAGO PRESS )  438 ( 1 ) L5 - L7   1995.01  [Refereed]

　View Summary

We observed a high-redshift luminous radio-quiet quasar Q1235+0857 at z = 2.880 with the Nobeyama 45 m radio telescope aiming at detection of a redshifted (CO)-C-12 (J = 3-2) emission line. We have marginally (3-5 sigma significance) detected an emission-line-like feature at similar to 89.8 GHz (z = 2.883) with similar to 150 km s(-1) width (FWHM). Adopting the standard CO to H-2 conversion factor obtained for galactic giant molecular clouds, the CO luminosity can be roughly converted to H-2 gas mass of similar to 10(12) M., which is much larger than the molecular gas content of any galaxies at preent epoch and nearly equal to the total stellar mass of a giant elliptical galaxy. Although we should note that a confirmation of the detection by an independent facility is absolutely needed, the results discussed in this Letter would support the idea that luminous quasars at high redshift are associated with the massive galaxies in their forming phase.

DOI

RADIAL-VELOCITY DISTRIBUTION OF THE GALAXIES IN THE PUPPIS HIDDEN CONCENTRATION BEHIND THE MILKY-WAY

T YAMADA, A TOMITA, M SAITO, P CHAMARAUX, KAZES, I

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY ( WILEY-BLACKWELL )  270 ( 1 ) 93 - 105   1994.09  [Refereed]

　View Summary

We investigate the radial velocity distribution of the galaxies in the Puppis region behind the Milky Way around (l, b) approximately (245-degrees, 0-degrees), where a concentration of galaxies was recently recognized through the systematic search for galaxies behind the zone of avoidance. Using the lower limit sample of the 60-mum flux-limited sample of IRAS galaxies brighter than f60 = 0.6 Jy, we find a large nearby clustering of galaxies at about 20 h-1 Mpc, whose peak spatial density at 7.5 h-1 Mpc scale is at least twice the whole-sky average. This Puppis concentration is probably associated with the S1 supercluster at (l, b) = (220-degrees, -15-degrees) detected in the QDOT survey, and this association is likely to be comparable to other nearby superclusters such as the Virgo, the Hydra, the Centaurus and the Fornax-Eridanus superclusters. Consequently, the effect of the Puppis concentration on the peculiar motions of the Local Group and other nearby galaxies should be considerable. There is no prominent individual cluster in the Puppis region, however, although some galaxies are concentrated into the regions around (l, b) = (245-degrees, -7-degrees) and (237-degrees, -15-degrees); the richness of these individual clusters in IRAS galaxies is as large as that of the Fornax cluster, and perhaps half or more of that of the Virgo cluster. We also study the radial velocity distribution of the galaxies selected by an optical limiting diameter, although uncertainty in the selection is large because of galactic extinction. The distribution of these diameter-selected galaxies shows good agreement with that of the IRAS-selected ones.

THE COMPLEX H-ALPHA VELOCITY-FIELD OF NGC-1569

A TOMITA, K OHTA, M SAITO （Part： Lead author )

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN ( ASTRONOMICAL SOC JAPAN )  46 ( 4 ) 335 - 341   1994  [Refereed]

　View Summary

We obtained an Her velocity field for the entire optical region of NGC 1569, a very actively star-forming dwarf irregular galaxy. The Ha velocities have two components with separations of several tens to one hundred km s(-1) at about one-fourth of the observed positions, and show bumpy features over the entire region. We suggest that these features are due to expanding bubbles. Kinematically, the peculiar 'Ha arm' feature is also part of a large-scale expanding bubble. We discuss some possible triggering mechanisms for the current star formation in NGC 1569.

SEARCH FOR CO EMISSION FROM THE DAMPED LYMAN-ALPHA SYSTEM TOWARD QSO 1215+333

K OHTA, T USUI, T YAMADA, T TAKATA, A TOMITA, N NAKAI

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN ( ASTRONOMICAL SOC JAPAN )  46 ( 4 ) L163 - L166   1994  [Refereed]

　View Summary

A search for redshifted (CO)-C-12 (J = 1-0) emission from the damped Lya system at z = 2.00 toward QSO 1215+333 was made. No emission was found, and the upper limit of the molecular-hydrogen mass is 1.6 x 10(11)h(-2)M. (q(0) = 0.5) if we assume a velocity width of 400 km s(-1) and the Galactic CO-to-H-2 conversion factor. We estimated the far-infrared luminosity from the HP luminosity, and found that the upper limit of the molecular-hydrogen mass and far-infrared luminosity are comparable to those of ultraluminous far-infrared galaxies. However, the upper limit of the molecular-hydrogen mass obtained in this system is much smaller than the molecular-hydrogen mass found in other damped Lya systems at z = 2-3. It seems that the star-formation properties in these damped Lya systems are quite different from those of the system toward QSO 1215+333 and nearby galaxies. Further observations of more damped Lya systems in CO lines as well as in other wavelengths are indispensable to trace the star-formation history of damped Lya systems.

4 ACTIVE GALAXIES NEWLY DETECTED BEHIND THE MILKY-WAY

T TAKATA, A TOMITA, T YAMADA, T TAKEUCHI, K NAKANISHI, M SAITO

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN ( ASTRONOMICAL SOC JAPAN )  46 ( 4 ) 343 - 347   1994  [Refereed]

　View Summary

In the course of our redshift; survey of IRAS galaxies behind the Milky Way, we newly detected four galaxies with active galactic nuclei, including one quasar and two Seyfert-type galaxies. The quasar, IRAS 07483+0328, is at z approximate to 0.1 and Mv = -24.0 mag. The quasar may be appropriate for investigating the nature of quasars because of its low redshift as well as the bright apparent magnitude.

Connection of Large-Scale Structure of the Galaxy Distribution behind the Southern Milky Way

Toru Yamada, Tadafumi Takata, Thomas Djamaluddin, Akihiko Tomita, Kentaro Aoki, Aki Takeda, Mamoru Saito

Monthly Notices of the Royal Astronomical Society   262 ( 1 ) 79 - 84   1993  [Refereed]

A search for IRAS galaxies behind the southern milky way

Toru Yamada, Tadafumi Takata, Thomas Djamaluddin, Akihiko Tomita, Kentaro Aoki, Aki Takeda, Mamoru Saito

Astrophysical Journal, Supplement Series ( University of Chicago Press )  89 ( 1 ) 57 - 84   1993  [Refereed]

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We systematically searched for IRAS galaxies with 60 μm flux density larger than 0.6 Jy by using the UK Schmidt Infrared and IIIa-J Atlases in the Milky Way region (|b| &lt
15°) between l = 210° and 360°. We first selected about 4000 IRAS point sources by using our far-infrared criteria, which are optimized for the search of IRAS galaxies behind the Milky Way region, and then inspected visually the optical counterparts of them on the Schmidt Atlas film copies. We found 966 IRAS sources associated with galaxy-like objects. The list of the objects is presented here with the IRAS source name, Galactic coordinates, IRAS flux densities, field number and emulsion of the Atlas, type and size of galaxy (-like) image, redshift, multiplicity, and cross-identification. Of these, 423 galaxies are already cataloged in the Catalog of Galaxies and Quasars Observed in the IRAS Survey, and most of the remaining 543 galaxy candidates are newly identified in this search. Although the radial velocities are known for only 387 galaxies, of which 60 were newly measured by us so far, we inferred the contamination by Galactic objects to be small from the good correlation between the sky distributions of the newly identified galaxy candidates and the previously cataloged galaxies. In the regions where the Galactic molecular clouds dominate, almost all the sources were not identified as galaxies. The detected galaxies are clustered in the three regions around l = 240°, 280°, and 315°, where the projected number densities are higher than the whole-sky average of IRAS galaxies of the same flux limit.

DOI

H-ALPHA VELOCITY-FIELDS OF GIANT H-II REGIONS IN 4 NEARBY DWARF IRREGULAR GALAXIES

A TOMITA, K OHTA, M SAITO （Part： Lead author )

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN ( ASTRONOMICAL SOC JAPAN )  45 ( 5 ) 693 - &   1993  [Refereed]

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We carried out Halpha spectroscopies of six giant H II regions in four isolated, nearby, face-on dwarf irregular galaxies: I Zw 36, NGC 6822, Sex A, and IC 1613. The Halpha velocity field maps were obtained for three galaxies, but not for IC 1613. These Halpha velocity fields have the following common features: (1) At the central parts of the H II regions the velocity fields are rather flat, i.e., the velocity ranges are 5 km s-1 or less over a scale of 50 to 200 pc. In particular, in the H II region in NGC 6822, observed with a spatial resolution of about 10 pc, the velocity field at the central part is more calm than that expected in gravitationally relaxed systems. (2) The Halpha velocities at the central parts axe nearly the same as the CO velocities, but several km s-1 larger than the velocities of H I gas surrounding the H II regions. (3) At the outer regions the Halpha velocities are shifted by 10 to 15 km s-1 from those at the central parts. By also considering the ages and locations of the H II regions as well as the extent of the H I envelopes, these features seem to be consistent with a model in which the star formation bursts are triggered by the collisions of infalling clouds with the H I disk.

CO-TO-H2 CONVERSION FACTOR IN DWARF IRREGULAR GALAXIES

K OHTA, A TOMITA, M SAITO, M SASAKI, N NAKAI

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN ( ASTRONOMICAL SOC JAPAN )  45 ( 2 ) L21 - L26   1993  [Refereed]

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(CO)-C-12 (J = 1-0) observations of five nearby dwarf irregular galaxies were made with a beam size of 15'', which is comparable to the size of a giant molecular cloud in the galaxies. We observed star-forming regions and/or H I clumps with a column density exceeding 10(21) cm-2, where molecular clouds tend to be detected. CO emission was detected toward two H I clumps in NGC 4214 and one clump in NGC 6822. For another three galaxies (IC 1613, Sex A, and GR 8) very low upper limits of the CO luminosity were obtained. We examined the relation between the CO luminosities and the line widths of molecular clouds in twelve galaxies, including other previous observations with a beam size comparable to the size of a giant molecular cloud and/or complex. The general tendency of this relation is that the CO luminosity for the same line width decreases with decreasing metallicity (O/H) of a galaxy; that is, if the line width is an indicator of the mass of a molecular cloud, the CO-to-H-2 conversion factor increases as the metallicity of a galaxy decreases. However, there is a large scatter in the CO luminosity among galaxies with the same metallicity; the conversion factors for dwarf irregular galaxies with the same metallicity are not always the same. For example, although NGC 6822 has a metallicity that is similar to those of IC 10 and the Small Magellanic Cloud, the CO luminosities of the molecular clouds axe much smaller than those in the other two galaxies and, thus, the conversion factor is considerably larger. The UV intensity in the star-forming region does not seem to be the main cause for this large scatter; some other factors may also affect the CO luminosity.