Takafumi Tsukui

ABOUT

Takafumi Tsukui

I am a Postdoctoral Fellow at Research School of Astronomy and Astrophysics (RSAA) in the Australian National University. You can read more about me in the RSAA newsletter.

I did my PhD at Graduate University for Advanced Studies, SOKENDAI and the National Astronomical Observatory of Japan. You can find my PhD thesis here titled "Formation and Evolution of Galactic Structures Using Gas and Stellar Kinematics".

I obtained my Bachelor in Physics at Tohoku University (Japan).

Research

Galaxy formation and evolution

I am interested in how galaxies have formed and evolved across cosmic time. The motion of star and gas within galaxies give us clues about how galaxies have evolved, how massive they are, and how galaxies will evolve.

My research focus is to elucidate the structure of galaxies from the early Universe to the current Universe, analysing gas and stellar kinematics measured by state-of-the-art telescopes such as the Atacama Large Millimeter/submillimeter Array (ALMA) and James Webb Space Telescope (JWST).

Fundamental Measurement Method

Signals from galaxies are extremely faint and can be overwhelmed by noise sources, such as radiation from Earth's atmosphere and thermal fluctuations of observation instruments. Therefore, a crucial aspect of research involves determining the probability of random noise mimicking a signal.

The astronomical images obtained through so-called interferometric observations exhibit complex correlation patterns that vary from one observation to another. Tsukui et al. 2023 address the fundamental understanding of the correlated noise in the image and propose flexible methods to assess the uncertainty of scientific results. Read more.

Publications

Link to Google scholar

First author

• T. Tsukui, E. Wisnioski, J. Bland-Hawthorn, K. Freeman 2024, Submitted to Monthly Notices of the Royal Astronomical Society, "The emergence of galactic thin and thick discs across cosmic history"
  NASA/ADS
• 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

• G. Santucci, C. Lagos, K. Harborne et al. (incl. T. Tsukui) 2024, Monthly Notices of the Royal Astronomical Society, Vol. 534, "The MAGPI survey: orbital distributions, intrinsic shapes, and mass profiles for MAGPI-like EAGLE galaxies using Schwarzschild dynamical models"
  NASA/ADS
• Y. Mai, S. Croom, E. Wisnioski et al. (incl. T. Tsukui) 2024, Monthly Notices of the Royal Astronomical Society, Vol. 533, "The MAGPI Survey: the evolution and drivers of gas turbulence in intermediate-redshift galaxies"
  NASA/ADS
• 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

• ESSENCE(NASA/ADS):
  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.
  
• Modified-stardust:
  A modified version of the Stardust code (Kokorev et al. 2021, ApJ, 921, 1) to incorporate the spatial decomposition of an image into a point source AGN and an extended host galaxy for galaxy spectral energy distribution modeling. This modified code is described and used in Tsukui et al. 2023, MNRAS, 523, 4654.
  

Presentations

• Sep. 2024, UNSW, School of Physics colloquium, NSW, Australia
  "The Emergence of Thin And Thick Disks Across Cosmic History"
• Aug. 2024, IAU General Assembly, Cape town, South Africa
  "The Emergence of Thin And Thick Disks Across Cosmic History"
• Aug. 2024, IAU General Assembly, Cape town, South Africa
  "Using ALMA as a Thermometer for Host Galaxy Growth of Quasar"
• Jul. 2024, Galaxy evolution colloquium, Oxford University, Oxford, England
  "Early Bar-disk Driven Galaxy Transformation at z~4.5"
• Jul. 2024, Special JWST seminar, University Observatory (LMU), Munich, Germany
  "Early Bar-disk Driven Galaxy Transformation at z~4.5"
• Jul. 2024, Galaxy coffee, ESO, Garching, Germany
  "Early Bar-disk Driven Galaxy Transformation at z~4.5"
• Jul. 2024, EAS Annual Meeting, Padova, Italy
  "The Emergence of Thin And Thick Disks Across Cosmic History"
• Jul. 2024, EAS Annual Meeting, Padova, Italy
  "Bar-Disk Driven Galaxy Formation in the Cosmic Morning"
• Jun. 2024, ELT Science in Light of JWST, Miyagi, Japan
  "The Emergence of Thin And Thick Disks Across Cosmic History"
• Dec. 2023, ALMA/45m/ASTE Users Meeting 2023, Mitaka, Tokyo, Japan
  "Galaxy transformation at z~4: insights from spatially resolved 4D (?) ALMA data"
• Nov. 2023, First Star First Galaxy, Sappro, Hokkaido
  "Disk-driven galaxy transformation at z=4: insights from spatially resolved ALMA data"
• Oct. 2023, 3D view of galaxies, ASTRO3D online seminar, Canberra, Australia
  "Evolution of a barred spiral galaxy at z~4; insights from spatially resolved 4D (?) ALMA data"
• Nov. 2023, The University of Tokyo colloquium, Bunkyo City, Tokyo
  "Disk driven galaxy transformation at z∼4: insights from spatially resolved 4D (?) ALMA data"
• Nov. 2023, Lunch talk, Kavli IPMU, Kashiwa Chiba
  "Spatially resolved dust properties and AGN-host decomposition for a starburst galaxy at z~4"
• Nov. 2023, Astrocoffee special talk, NAOJ, Tokyo, Japan
  "Disk-driven galaxy transformation at z~4; insights from spatially resolved 4D(?) ALMA data"
• Nov. 2023, Obsap colloquium, Waseda University, Shinjuku, Tokyo
  "Spatially resolved dust properties and quasar-galaxy decomposition of HyLIRG at redshift 4.4"
• 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, ASTRO3D galaxy kinematics workshop, Canberra, Australia
  "Spiral Galaxies at z=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, Tsukuba Univ. Theoretical Astrophysics group colloquium, 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 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

ANU / NAOJ / Kagoshima University Press release : "A Dancing Ancient Galactic Disk at a Peak of Star Formation"

ASTRO3D Press release : "Heat spot reveal growth rate of a galaxy 12 billion years ago"

SOKENDAI Publication Grant article : "Error analysis method under correlated noise in interferometric images"

NAOJ press release : "ALMA Discovers the Most Ancient Galaxy with Spiral Morphology"

Contact

Email: tsukuitk23 [at] gmail [dot] com

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

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