Takafumi Tsukui

ABOUT

津久井崇史

04/2022 - オーストラリア国立大 天文専攻 博士研究員

04/2017 - 03/2022: 総合研究大学院大学/国立天文台 天文科学専攻(博士課程)

博士論文"ガスおよび星の動力学を用いた銀河の構造形成とその進化の解明"はこちらから読めます。

04/2020 - 03/2022: 国立天文台ジュニアフェロー

09/2017 - 03/2020: 国立天文台准研究員

04/2013 - 04/2017: 東北大学 理学部 宇宙地球物理学科

04/2010 - 03/2013: 群馬県立太田高等学校

Research

Galaxy formation and evolution

宇宙全体の歴史において、銀河がどのようにでき、現在観測されるような銀河へと成長してきたのかを解明すべく研究をしています。特に、銀河内に存在する星やガスの運動は銀河の形成や進化に影響を与えた物理過程の痕跡、銀河の質量分布構造、そしていかに進化していくのかを探る重要な手がかりを与えてくれます。

私はアルマ望遠鏡やVLT望遠鏡などの高い分解能と感度を持つ望遠鏡で銀河を観測し、銀河のガスの運動と星の運動を解析することで、宇宙の歴史全体に渡った銀河構造進化の変遷を解き明かすことをテーマに研究しています。

Noise in the astronomical images

天体からの光は非常に弱いため、データから導き出される結論や、解析結果は地球の大気からの放射光や、観測装置の熱雑音などに起因するノイズの影響を受けます。そのため、データを正しく解釈する上で、ノイズの影響を正しく見積もることが重要です。

干渉計観測と呼ばれる複数のアンテナでの同時観測によって得られる天体画像は、その複雑な画像合成手法(コンピュータによるフーリエ変換によって画像を復元する)により、観測ごとに異なる複雑な相関パターンを持っています。Tsukui et al. 2023では干渉計画像に含まれるノイズの統計的な性質を明らかにし、データ解析におけるノイズの影響を正しく見積もる手法を提案しました。

Publications

Link to Google scholar

First author

• T. Tsukui, E. Wisnioski, J. Bland-Hawthorn, Y. Mai et al. 2024, Monthly Notices of the Royal Astronomical Society, Vol 527, "Detecting a disk bending wave in a barred-spiral galaxy at redshift 4.4"
  NASA/ADS
• T. Tsukui, E. Wisnioski, M. R. Krumholz, A. Battisti 2023, Monthly Notices of the Royal Astronomical Society, Vol. 523, "Spatially resolved dust properties and quasar-galaxy decomposition of a hyper-luminous infrared galaxy at z=4.4"
  NASA/ADS
• T. Tsukui, S. Iguchi, I. Mitsuhashi, and K. Tadaki 2023, Journal of Astronomical Telescopes, Instruments, and Systems, Vol. 9, "Estimating the statistical uncertainty due to spatially correlated noise in interferometric images"
  NASA/ADS
• T. Tsukui, and S. Iguchi 2021, Science, Vol. 372, "Spiral morphology in an intensely star-forming disk galaxy more than 12 billion years ago"
  Free access to the article / NASA/ADS
  

Co-author

• Q. Chen, K. Grasha, A. Battisti et al. (incl. T. Tsukui) 2024, Monthly Notices of the Royal Astronomical Society, Vol. 527, "The MAGPI survey: effects of spiral arms on different tracers of the interstellar medium and stellar populations at z 0.3"
  NASA/ADS
• L. Maud, Y. Asaki, H. Nagai, T. Tsukui, et al. 2023, The Astrophysical Journal Supplement Series, Vol. 267, "ALMA High-frequency Long-baseline Campaign in 2019: Band 9 and 10 In-band and Band-to-band Observations Using ALMA's Longest Baselines"
  NASA/ADS
• R. Ikeda, T. Morishita, T. Tsukui, et al. 2023, Monthly Notices of the Royal Astronomical Society, Vol. 523, "Near-infrared characterization of ultra-diffuse galaxies in Abell 2744 by JWST/NIRISS imaging"
  NASA/ADS
• D. D. Nguyen, M. Bureau, S. Thater et al. (incl. T. Tsukui) 2022. Monthly Notices of the Royal Astronomical Society, Vol. 509, "MBHBM* Project. II. Molecular Gas Kinematics in the Lenticular Galaxy NGC 3593 Reveal a Supermassive Black Hole"
  NASA/ADS
• D. D. Nguyen, M. den Brok, A. C. Seth et al. (incl. T. Tsukui) 2020. The Astrophysical Journal, Vol. 892, "The MBHBM* Project. I. Measurement of the Central Black Hole Mass in Spiral Galaxy NGC 3504 Using Molecular Gas Kinematics"
  NASA/ADS
• D. D. Nguyen, A. C. Seth, N. Neumayer, et al. (incl. T. Tsukui) 2019. The Astrophysical Journal, Vlo. 872, "Improved Dynamical Constraints on the Masses of the Central Black Holes in Nearby Low-mass Early-type Galactic Nuclei and the First Black Hole Determination for NGC 205"
  NASA/ADS

Proceedings

• T. Tsukui, S. Iguchi, I. Mitsuhashi, and K. Tadaki, the Proceedings of the SPIE, Astronomical Telescopes and Instrumentation 2022, Paper Number: 12190-92, "Proper evaluation of spatially correlated noise in interferometric images"
  SPIE Digital Library

Codes

• T. Tsukui 2023 ESSENCE:
  A python package for evaluating the statistical significance of the image analysis and signal detection under correlated noise in the interferometric images (e.g., ALMA, NOEMA), namely, Evaluating Statistical Significance undEr Noise CorrElation.
  NASA/ADS

Presentations

• Aug. 2023, Asia-Pacific Regional IAU Meeting, Fukushima, Japan
  "Using ALMA as a thermometer for AGN diagnostics and galaxy evolution"
• Jul. 2023, European Astronomical Society Annual Meeting, Krakow, Poland
  "Estimating the statistical uncertainty due to spatially correlated noise in interferometric images"
• Jul. 2023, Galactic bars: driving and decoding galaxy evolution, Granada, Spain
  "Bar-driven galaxy evolution at redshift 4.4?"
• May. 2023, New Eyes on the Universe: SKA & ngVLA, Vancouver, Canada
  "Estimating the statistical uncertainty due to spatially correlated noise in interferometric images"
• Apr. 2023, The Kavl Institute for Astronomy and Astrophysics seminar, Peking, China
  "Using ALMA as a thermometer for black hole and galaxy co-evolution"
• Mar. 2023, Bears ALMA Proposal Workshop, Tokyo, Japan
  "Spatially resolved ISM properties and AGN-galaxy decomposition of HyLIRG at redshift 4.4"
• Feb. 2023, 9th Galaxy Evolution Workshop, Kyoto Univ. Kyoto, Japan
  "Spatially resolved ISM properties and AGN-galaxy decomposition of HyLIRG at redshift 4.4"
• Dec. 2022, ALMA/45m/ASTE Users Meeting 2022, Mitaka, Tokyo, Japan
  "Proper evaluation of spatially correlated noise in interferometric images"
• Jul. 2022, SPIE Astronomical Telescopes + Instrumentation Montréal, Québec, Canada
  "Proper evaluation of spatially correlated noise in interferometric images"
• Aug. 2022, IAU General Assembly, Koria, Busan
  "Spiral disk with concentrated central mass in a Hyper Luminous Infrared Galaxy at a redshift of 4.4"
• Jun. 2022, 240th Meeting of the American Astronomical Society Pasadena, California, USA
  "Starbursting" disk with a spiral morphology in a Hyper Luminous Infrared Galaxy at redshift of 4.4"
• Mar. 2022, Astronomical Society of Japan, spring meeting
  "Internal strucutre of dusty starburst galaxy BRI1335 revealed by ALMA [CII] gas kinematics"
• Sep. 2021, Univ. of Tsukuba Theoretical Astrophysics Group Tsukuba Uchu Forum, Ibaraki, Japan
  "Identifying galactic structures in a galaxy more than 12 billion years ago using the gas dynamics"
• Jun. 2021, Osaka Univ. Theoretical AstroPhysics Group (OUTAP) Colloquium, Osaka, Japan
  "Rotating gas dynamics and spiral morphology in a galaxy at redshift 4.4"
• Sep. 2019, next-generation VLA workshop, Tokyo, Japan
  "HI gas kinematics for SMBH, Bulge and Disk, and Dark matter in the mass assembly history of galaxies"
• Oct. 2019, ALMA2019: Science Results and Cross-Facility Synergies, Sardinia, Italy
  "Galactic Dynamics and Dark Matter Profile of NGC1380 with ALMA and VLT/MUSE"
• Jul. 2019, IAUS 353: Galactic Dynamics in the Era of Large Surveys, Shanghai, China
  "The measurement of Dark Matter profile of NGC1380 with ALMA and VLT/MUSE"
• Oct. 2018, Armagh Observatory and Planetarium Seminal Talk, Northern Ireland, UK
  "Central Black Hole Measurement using Molecular gas dynamics of NGC1380"

Press release

オーストラリア国立大/国立天文台/鹿児島大のプレスリリース: "若い銀河円盤に伝わる地震波を検出"

ASTRO 3D メディアリリース : "ヒートスポットが明かす宇宙初期銀河の成長の描像"

総研大論文出版助成記事: "干渉計画像に存在する相関ノイズの下でのエラー解析"

国立天文台のプレスリリース: "観測史上最古、124億年前の宇宙に渦巻き構造を持つ銀河を発見"

Contact

メールアドレス: tsukuitk23 [at] gmail [dot] com

住所: Research School of Astronomy & Astrophysics Mount Stromlo Observatory Cotter Road Weston Creek, ACT 2611 Australia

Github Twitter

Elements

i = 0;

while (!deck.isInOrder()) {
    print 'Iteration ' + i;
    deck.shuffle();
    i++;
}

print 'It took ' + i + ' iterations to sort the deck.';