筑波大学 宇宙物理学研究室 森正夫
Theoretical Astrophysics and Computational Physics

Preface

Welcome to the website of the astrophysics research team led by Masao Mori at the University of Tsukuba. Our team advances astrophysics by combining numerical simulations, analytical theory, and observational data analysis. Research topics include galaxy formation and evolution, the role of dark matter in cosmic structure formation, galaxy collisions, supermassive black hole activity, galactic winds, and habitable zones within galaxies.

We specialise in computational astrophysics, developing large-scale simulations and theoretical models to study the complex dynamics of galaxies. Our work integrates closely with observational research, bridging theory and data to build a unified understanding of the universe. We develop high-performance hydrodynamic schemes, massively parallel algorithms, and GPU-accelerated methods, and have recently begun incorporating machine learning to further enhance astrophysical modelling.

Portrait
Campus

We are dedicated to nurturing the next generation of astrophysicists. Our group welcomes both undergraduate and graduate students, offering opportunities to participate in cutting edge research. At the University of Tsukuba, graduate school entrance examinations are held three times a year: a recommendation based exam in July, and general admissions in August and February. We actively encourage applications from students at other universities as well.

Please note that acceptance depends strongly on the current situation of the laboratory, including supervision capacity, funding, and project availability. Before starting any application process, please contact us to confirm whether we can host a new student and to discuss fit with ongoing projects.

Masao Mori

Team 2025

Research

My research activities so far

“How did the cosmos begin, and how did it become what it is today?” — this fundamental question has captivated humanity since ancient times. Cosmology and astrophysics seek to answer it through the lens of physics. George Gamow’s theory (Gamow 1984) laid the foundation for modern discussions on the universe’s origin and has guided observational efforts throughout the 20th and 21st centuries. Today, it is widely accepted that the universe began 13.8 billion years ago in a hot, dense state—the Big Bang—and that the formation and evolution of celestial structures in the expanding universe have shaped the cosmos we observe.
Our research group aims to uncover how galaxies have evolved over cosmic time and to explore their future, grounded in the principles of natural science.

Shanghai

Activities

What's new

This section highlights our latest research activities, including publications, conference presentations, media coverage, and collaborative projects. We also share updates on team events and extracurricular activities that strengthen connections and promote a healthy work-life balance within the group.

  • Nov. 24 to Dec. 13, 2025
    Misa Yamaguchi (Ph.D. student, 1st year) is staying at Zhejiang University in Hangzhou, China, to conduct research on galaxy evolution.
  • Nov. 29, 2025
    Our coauthored paper with Koki Ohtaki (University of Rome) and Yudai Kazuno (MSc 2022), Collision frequency between dark matter subhaloes within Milky Way-like galaxies, has been published online in New Astronomy. [New Astronomy / arXiv:2511.16464]
  • Nov. 20, 2025
    Our coauthored paper with Koki Ohtaki (University of Rome) and Yudai Kazuno (MSc 2022), Collision frequency between dark matter subhaloes within Milky Way-like galaxies, has been accepted for publication in New Astronomy. [arXiv:2511.16464]
About Image

About me

Who I am

Masao Mori

Ph.D. (Science), Associate Professor

  • Visiting Associate Professor, University of California, Los Angeles (Feb. 2005 - Mar. 2006)
  • Visiting Researcher, Max Planck Institute for Astronomy (Aug. 1998 - Aug. 1999)
Team 2025

Our Team

Group members for this year and graduates

Below, you will find information about my current team members and graduates.

Current Members

  • Yuka Kaneda(PhD student, 3rd year and Master's Program in Computer Science, 2nd year)
    JSPS Special Research Fellow DC1 and University of Tsukuba, Dual Degree Programme
    Challenges to the Cold Dark Matter Hypothesis (3rd-year Ph.D student in Physics)
    Structural Analysis of Stellar Streams Using Machine Learning (2nd-year master's student in Infomatics)
  • Misa Yamaguchi(PhD student, 1st year)
    Research Fellow, JST SPRING Program for Challenging Exploratory Research
    Galaxy Collisions and Evolution of the Galactic Habitable Zone
  • Taisei Takeuchi (MSc student, 2nd year)
    Formation of Star Clusters and Dark Matter Halos in the M81 Galaxy Group
  • Kotaro Hiraki (Master’s Program in Education, 2nd year)
    Educational Applications through Visualisation of Astrophysical Simulations
  • Kanta Aimoto (MSc student, 1st year)
    Hydrodynamical Interactions in Collisions between Satellite Galaxies and Galactic Disks
  • Mayuka Oda (MSc student, 1st year)
    Scaling Relations of Massive Dark Matter Halos
  • Michi Shinozaki (MSc student, 1st year)
    Critical Conditions for Cusp-Core Transitions in Dark Matter Halos
  • Yoshitomo Takahashi (MSc student, 1st year)
    Development of High-Precision Hydrodynamic Simulation Schemes and Their Applications to Galaxy Formation
  • Akifumi Takayama (MSc student, 1st year)
    Galaxy Mergers and Activity of Supermassive Black Hole
  • Maria Arima (Undergraduate student, 4th year)
    Transonic Galactic Winds in High-Redshift Galaxies
  • Taisei Nomura (Undergraduate student, 4th year)
    Formation of Parallel Stellar Streams in the Halo of the Andromeda Galaxy
  • Kenta Hagiwara (Undergraduate student, 4th year)
    Sports Science Research Utilizing Large-Scale Hydrodynamic Simulations

Achievements

Achievements

A summary of my research Highlights

Below is a list of my recent research papers, selected papers to date, and received research funding.

Recent publications

  • The Characteristic Mass and Energy Conversion Efficiency in the Cusp-Core Transition of Dark Matter Haloes: Implications for Scaling Relations and Supernova feedbacks,
    Shinozaki, Michi; Mori, Masao; Kaneda, Yuka; Hayashi, Kohei, submitted to Monthly Notices of the Royal Astronomical Society.
  • Splitting a Stellar Stream, Bridging Luminous and Dark Domains,
    Kaneda, Yuka; Mori, Masao; Miki, Yohei; Kirihara, Takanobu; Burkert, Andreas, submitted.
  • Accelerated Hermite integrator for orbital integration with OpenACC and MPI,
    Otaki, Koki; Mori, Masao; Miki, Yohei; Takahashi, Daisuke, submitted to the Journal of Supercomputing.
Lecture Room

Lectures

Lectures for this academic year

FY2025

  • Undergraduate Programms
    • General concept of astrophysics: Fall AB, Fri. 4
    • Hands-on Seminar for Research Exploration
    • Diploma thesis research advice

  • Postgraduate Programmes
    • Fundamental Physics 2: Fall AB, Mon. 3
    • Special Research in Astrophysics
    • Master thesis advice
    • Doctor thesis advice

  • Seminars
    • Mori's Group Seminar
    • Galaxy Seminar
    • Fundermental Physics Seminar B

Contact

Contact

Feel free to contact

mmori@ccs.tsukuba.ac.jp

Center for Computational Sciences, University of Tsukuba
Tennodai 1-1-1, Tsukuba, Ibaraki 305-8577, Japan

+81 (0)29 853 6034