Chikako Ishizuka
Nuclear Energy Division
- Position
- Associate Professor
- TEL
- +81-3-5734-3061
- ishizuka.c.686am.isct.ac.jp
Feature of Research
Our laboratory aims to support the development of safe, sustainable, and socially acceptable nuclear systems to help solve the world’s energy challenges, and to promote GX. We focus especially on the practical use of nuclear reactions for both energy and medical applications. Among our core projects is the design of a molten-salt fast reactor with high transmutation efficiency—comparable to Japan’s Monju reactor—which automatically reduces its power output as internal temperatures rise, offering an inherently safe response to abnormal situations.
Outline of Research
- Nuclear Data
Nuclear data play a key role in designing and operating nuclear systems. They are used in many fields, such as fusion and fission energy, radioactive waste transmutation, radiation therapy, and cosmic-ray exposure studies. These data are collected through experiments and theoretical models, then compiled into evaluated nuclear data libraries. One major challenge is dealing with uncertainties in the data. In our lab, we study the entire process from nuclear theory and data evaluation to how uncertainties affect real-world applications. Our goal is to build a reliable link between theory and practical use. - Nuclear Reactions and Their Uncertainties
To improve nuclear data quality, we need reliable values from theory or experiments. Because we don’t know the precise potential form of nuclear force, we need to select different model depending on the reaction system. Our lab works on developing and using various theoretical approaches, such as the Multidimensional Langevin Model, AMD, and TDDFT. We also study data uncertainty using machine learning and the Total Monte Carlo (TMC) method supported by the IAEA’s T6 code. - Nuclear Transmutation and Molten-Salt Fast Reactors
Nuclear energy is gaining interest as a stable, low-carbon power source. Following the Fukushima accident, there's a strong need for reactor systems that are inherently safe and can prevent overheating, even unexpectedly. Our lab is researching new reactor designs that are naturally safer. We are specifically looking at "chloride molten-salt fast reactors." We study how these reactors work, their safety features, and how they can change nuclear waste. We believe these reactors will be important for future energy, offering clean, stable power and helping to reduce radioactive waste. - Heavy-Ion Cancer Therapy
Heavy-ion therapy is a advanced cancer treatment that uses high-energy carbon to precisely destroy tumors. However, current simulation tools like PHITS and Geant4 don't fully account for the quantum behavior of nucleons. Our lab is improving these tools by adding the Antisymmetrized Molecular Dynamics (AMD) model. This will lead to more accurate predictions for treatment planning, helping to create safer and more effective cancer therapies. 5. - Cosmic-Ray Exposure
Space radiation exposure is over 100 times higher than on Earth, making accurate dose assessment crucial for astronaut safety. Japan has pioneered the PHITS simulation code for cosmic-ray exposure, which uses detailed nuclear reaction models. Cosmic rays come from charged particles made by stars and supernovae. PHITS uses the JAM model for high-energy processes, but it wasn't originally optimized for space. Our lab is now collaborating with JAM developers to improve its accuracy specifically for space radiation. This will greatly enhance our ability to predict radiation doses in space.
Keyword
Nuclear Data, Nuclear Reactions, Nuclear Transmutation, Uncertainty, Nuclear theory, Nuclear-astrophysics