Tanaka, Kunihiko

写真a

Affiliation

Faculty of Science and Technology, Department of Physics ( Yagami )

Position

Research Associate/Assistant Professor/Instructor

External Links

Career 【 Display / hide 】

  • 2005.04
    -
    2008.03

    University of Tokyo, Institute of Astronomy

  • 2008.04
    -
    2008.09

    National Astronomical Observatory Japan, Nobeyama Radio Observatory, PD

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Research Areas 【 Display / hide 】

  • Natural Science / Astronomy

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Research Keywords 【 Display / hide 】

  • Radio Astronomy

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Research Themes 【 Display / hide 】

  • 銀河系中心、大質量星形成、近傍銀河, 

    2005.04
    -
    Present

    　View Summary

    Galactic Center, Massive Star Formation, Nearby Galaxies

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Papers 【 Display / hide 】

  • ALMA [CI] Image of the Circumnuclear Disk of the Milky Way: Inflowing Low-density Molecular Gas

    Kunihiko Tanaka, Makoto Nagai, Kazuhisa Kamegai

    The Astrophysical Journal (IOP science)   2026

    Research paper (scientific journal), Joint Work, Lead author, Accepted

  • The LMT 2 millimeter receiver system (B4R). II. Science demonstration observations toward Orion-KL/OMC-1

    Yonetsu T., Kawabe R., Yoshimura Y., Taniguchi K., Shimajiri Y., Rojas-García O.S., Gómez-Ruiz A.I., Sakai T., Tanaka K., Hatsukade B., Taniguchi A., Tamura Y., Takekoshi T., Oshima T., Kohno K., Hagimoto M., Hughes D.H., Schloerb F.P., Sánchez-Argüelles D., Souccar K., Narayanan G., Yun M.S., Gómez-Rivera V., Rodríguez-Montoya I., Colín-Beltrán E., Chávez Dagostino M., Zaragoza-Cardiel J., Fujita S., Maezawa H.

    Publications of the Astronomical Society of Japan 77 ( 6 ) 1224 - 1258 2025.12

    ISSN  00046264

    　View Summary

    We present the results of mapping and single-point spectral scans toward Orion-KL/OMC-1 performed as science demonstrations of a 2mm superconductor–insulator–superconductor receiver, named the Band 4 Receiver (B4R), installed on the Large Millimeter Telescope (LMT), with a diameter of 50m. To prove the capabilities of mapping and spectral scans with the B4R on the LMT, commissioning observations were conducted employing the on-the-fly mapping technique toward Orion-KL/OMC-1, which covers a map size of 5′ × 5′. These mapping observations were performed with two frequency settings providing 10GHz in total (131.4–133.9 and 145.1–147.6GHz; 136.2–138.7 and 149.9–152.4GHz) with a frequency resolution of 76.293kHz. In this study, we conducted spectral line identification analysis for the hot core and compact ridge regions in the Orion-KL with a beam size of 11″–12″. We detected nearly 400 emission lines and identified two recombination lines and 29 molecular species, including isotopologues, deuterated molecules, and vibrational excited states, despite the short integration time. These results of line detection are consistent with those of previous studies. The 29 molecular species include nitrogen (N)-bearing complex organic molecules (COMs) and oxygen (O)-bearing COMs. To demonstrate the capability of the B4R in astrochemistry, we conducted detailed analyses of column densities, rotational temperatures, and relative abundances with respect to H<inf>2</inf> on two representative COMs, N-bearing C<inf>2</inf>H<inf>5</inf>CN and O-bearing CH<inf>3</inf>OCHO in the central 40″ × 40″ area of the map. The wide bandwidth of 10GHz enabled the use of 8 and 34 emission lines, respectively. The spatial differences in the physical and chemical properties between the above two molecules were derived at a spatial resolution of ∼12″. The B4R on the LMT was successfully demonstrated to be powerful for mapping and spectral scans and to have high potential for the study of interstellar chemistry.

  • The LMT 2 Millimeter Receiver System (B4R). I. Overview and Results of Science Demonstration

    Ryohei Kawabe, Takeshi Sakai, Kunihiko Tanaka, Akio Taniguchi, Bunyo Hatsukade, Yoichi Tamura, Yuki Yoshimura, Tatsuya Takekoshi, Tai Oshima, Masato Hagimoto, Teppei Yonetsu, Kotomi Taniguchi, Kotaro Kohno, Hiroyuki Maezawa, David H. Hughes, Peter F. Schloerb, Edgar Colín-Beltrán, Miguel Chávez Dagostino, Víctor Gómez-Rivera, Arturo I. Gómez-Ruiz, Gopal Narayanan, Iván Rodríguez-Montoya, David Sánchez-Argüelles, Yoshito Shimajiri, Kamal Souccar, Min S. Yun, Tom J. L. C. Bakx, Kevin C. Harrington, Shinji Fujita, Fumitaka Nakamura, O. S. Rojas-García, Alfredo A. Montaña Barbano, Javier Zaragoza-Cardiel

     2025.11

    　View Summary

    We report on the results of the on-sky test and science demonstration conducted with the 2 mm receiver system, B4R, on the 50 m Large Millimeter Telescope (LMT), located at an altitude of 4600 m in Mexico. The B4R receiver was developed based on the dual-polarization sideband-separating mixer technology of the Atacama Large Millimeter/submillimeter Array, and is equipped with a fast Fourier transform digital spectrometer, XFFTS. The primary science objective is the spectroscopic redshift identification of high-redshift dusty star-forming galaxies, complementing the existing 3 mm Redshift Search Receiver by enabling the detection of multiple carbon monoxide lines. Additionally, the B4R receiver broadens the range of science cases possible with the LMT, including astrochemistry, as the 2 mm band encompasses unique molecular lines such as deuterated molecules and shock tracers. During on-site commissioning in 2018 and 2019, we successfully demonstrated on-the-fly mapping and position-switching observations toward the Orion Molecular Cloud 1 and bright high-redshift dusty star-forming galaxies, respectively. We confirmed that the installed B4R system largely met its basic performance specifications. Furthermore, we measured the LMT's aperture efficiencies across the entire B4R frequency range (130-160 GHz), finding them to be roughly consistent with expectations based on a surface accuracy of 100 $μ$m and the receiver optics design. These results with the B4R will enable the most sensitive single-dish spectroscopic observations at 2 mm using the LMT.

  • Shock-induced HCNH+ abundance enhancement in the heart of the starburst galaxy NGC 253 unveiled by ALCHEMI

    Y. Gong, C. Henkel, C. T. Bop, J. G. Mangum, E. Behrens, F. J. Du, S. B. Zhang, S. Martin, K. M. Menten, N. Harada, M. Bouvier, X. D. Tang, K. Tanaka, S. Viti, Y. T. Yan, W. Yang, R. Q. Mao, D. H. Quan

    Astronomy and Astrophysics  2025

    Joint Work, Accepted

  • Spatially-resolved spectro-photometric SED Modeling of NGC 253's Central Molecular Zone I. Studying the star formation in extragalactic giant molecular clouds

    Humire, Pedro K. ; Dey, Subhrata ; Ronconi, Tommaso ; Sasse, Victor H. ; Cid Fernandes, Roberto ; Martín, Sergio ; Donevski, Darko search by orcid ; Małek, Katarzyna ; Fernández-Ontiveros, Juan A. ; Song, Yiqing ; Hamed, Mahmoud ; Mangum, Jeffrey G. ; Henkel, Christian ; Rivilla, Víctor M. ; Colzi, Laura ; Harada, N. ; Demarco, Ricardo ; Goyal, Arti ; Meier, David S. ; Panda, Swayamtrupta ; Krabbe, Ângela C. ; Yan, Yaoting ; Lopes, Amanda R. search by orcid ; Sakamoto, K. ; Muller, S. ; Tanaka, K. ; Yoshimura, Y. ; Nakanishi, K. ; Kanaan, Antonio ; Ribeiro, Tiago ; Schoenell, William ; Mendes de Oliveira, Claudia

    Astronomy and Astrophysics  2025

    Research paper (scientific journal), Joint Work, Accepted

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Papers, etc., Registered in KOARA 【 Display / hide 】

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Presentations 【 Display / hide 】

  • Star Formation Conditions In the Milky Way’s Galactic Central Molecular Zone

    TANAKA Kunihiko

    [International presentation]  Star Formation in Different Environments 2017, 

    2017.08

  • Search for the CO-dark Mass in the Central Molecular Zone by using the ASTE 10-m Telescope

    TANAKA Kunihiko

    IAUS 322: The Multi-Messenger Astrophysics of the Galactic Centre, 

    2016.07
    , 

    Oral presentation (general)

  • CO-0.30-0.07: A Candidate Site of Collision-induced Massive Star Formation in the Milky Way's Central Molecular Zon

    TANAKA Kunihiko

    [International presentation]  The 6th Zermatt ISM Symposium",, 

    2015.09
    , 

    Oral presentation (general)

  • Giant Molecular Clouds with High Abundance of Atomic Carbon and Cyano Radical in the Milky Way's Central Molecular Zone

    TANAKA Kunihiko

    [International presentation]  IAU General Assembly, Meeting #29 (Honolulu, HA, USA) , 

    2015.08
    , 

    Poster presentation, International Astronomical Union

  • The ASTE Galactic Center Survey in the 350 and 500 GHz Bands

    TANAKA Kunihiko

    [International presentation]  New Trends in Radio Astronomy in the ALMA Era / the 30th Anniversary of Nobeyama Radio Observatory (Hakone, Kanagawa, Japan) , 

    2012.12
    , 

    Oral presentation (general)

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Research Projects of Competitive Funds, etc. 【 Display / hide 】

  • 銀河系中心領域での局所的な爆発的星形成現象

    2016.04
    -
    2019.03

    日本学術振興会, Grant-in-Aid for Scientific Research, Research grant, Principal investigator

  • ミリ波－サブミリ波観測で探る銀河系中心活動性

    2014.04
    -
    2016.03

    日本学術振興会, Grant-in-Aid for Scientific Research, Research grant, Principal investigator

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Works 【 Display / hide 】

  • 夏の星空から始める天文学：銀河系中心の不思議な天体たち

    田中邦彦

    朝日カルチャーセンター, 

    2013.08
    , 

    Other

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Courses Taught 【 Display / hide 】

  • PHYSICS LABORATORIES 2

    2025

  • PHYSICS LABORATORIES 1

    2025

  • PHYSICS B

    2025

  • LABORATORY IN SCIENCE

    2025

  • PHYSICS LABORATORIES 2

    2024

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Memberships in Academic Societies 【 Display / hide 】

  • Astronomical Society Japan

    　
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