[English, Japanese]

---

Koichi Hamaguchi

HEP Theory Group, Department of Physics, University of Tokyo

• seminars and journal clubs
• members
• Postdoc position

publications ( INSPIRE, arXiv ),        CV

Lectures

New Physics Forum

Research Interest

Physics beyond the Standard Model of Particle Physics, its application to cosmology (baryogenesis, Dark Matter and its signatures, Inflation), Supersymmetric Models.

Contact

Koichi Hamaguchi
Department of Physics, University of Tokyo, Tokyo 113-0033, Japan
Faculty of Science Bldg.1., Hongo Campus (room 916)   [Access]
Email: hama _ at _ hep-th.phys.s.u-tokyo.ac.jp
Phone: +81-(0)3-5841-7640
Fax: +81-(0)3-5841-4224

For prospective JSPS Postdoctoral Fellowship applicants:

• UNOFFICIAL Guide to the JSPS Postdoctoral Fellowship (Standard)
• Applying with Koichi Hamaguchi as the host

For international (prospective) students:

• For those who are interested in doing research with Koichi Hamaguchi as graduate students
• UNOFFICIAL guidelines for JSPS DC fellowship application in English

---

Recent Papers (2024-):

• Gamma-Ray Signatures of Thermal Misalignment Dark Matter
  K. Hamaguchi, R. Hayakawa, H. Takahashi     arXiv: 2604.05326   

• Revisiting Bino-Slepton Coannihilation Dark Matter in Light of Recent Experimental Results
  K. Hamaguchi, A. Niki, K. H. To     arXiv: 2603.18412   

• Affleck-Dine Leptoflavorgenesis
  K. Akita, K. Hamaguchi, M. Ovchynnikov,     arXiv: 2509.08175   

• Maximal parameter space of sterile neutrino dark matter with lepton asymmetries
  K. Akita, K. Hamaguchi, M. Ovchynnikov,     arXiv: 2507.20659   

• Axion Emission from Proton Cooper Pairs in Neutron Stars
  K. Hamaguchi, N. Nagata, J. Zheng,     arXiv: 2502.18931   

• Insights on the Scale of Leptogenesis from Neutrino Masses and Neutrinoless Double-Beta Decay
  A. Granelli, K. Hamaguchi, M. E. Ramirez-Quezada, K. Shimada, J. Wada, T. Yokoyama,     arXiv: 2502.10093   

• Wormhole-Induced ALP Dark Matter
  D. Y. Cheong, K. Hamaguchi, Y. Kanazawa, S. M. Lee, N. Nagata, S. C. Park,     arXiv: 2411.07713   

• Exploring Chirality Structure in Nucleon Decay
  K. Hamaguchi, S. Hor, N. Nagata, H. Takahashi,     arXiv: 2409.08747   

• A Generic Analysis of Nucleon Decay Branching Fractions in Flipped SU(5) Grand Unification
  K. Hamaguchi, S. Hor, N. Nagata, H. Takahashi,     arXiv: 2407.11892   

• All papers:  INSPIRE, arXiv

---

Workshops/Conferences

• 2026
  • CAU-IBS BSM 2026 (6/7-)
  • SI 2026 (8/7-)
  • PPC 2026 (8/31-)
  • NEXUS 2026 (9/9-)
  • JPS 2026 (9/14-)
  • AEPSEHP 2026 (10/14-)
• 2025
  • 第5回 研究用原子炉を用いた原子核素粒子物理学 (12/9-)
  • 2025 CERN-CKC joint workshop with the 13th KIAS Workshop on Particle Physics and Cosmology (11/16-)
  • The Future is Whispering (6/25-)
  • 第1回 学術変革「地下稀事象」若手研究会 + 第10回「極低放射能技術」研究会 (3/6-)
  • 第11回超新星ニュートリノ研究会 (3/3-)
  • Iwate Collider School 2025 (2/24-)
  • KEK-PH 2025 (2/18-)
  • Nucleosynthesis and Evolution of Neutron Stars (1/27-)
• 2024
  • Hitoshi Fest @ Kavli IPMU (12/16-)
  • The 15th Particle Physics Phenomenology Workshop (PPP15) (10/21-)
  • The 4th DMNet symposium (9/5-)
  • LCWS 2024 (7/8-)
  • FLASY2024 (6/24-)
  • 将来コライダー実験に向けた共同研究 (6/12)
  • New Physics Directions in the LHC Era and Beyond (4/22-)
  • Berkeley week (3/11-)
  • UGAP2024 (3/4-)
  
  
• before 2023