Radichemistry Group

Radiochemistry Group conducts the studies on activation in the high-energy accelerator facility.

Purpose and Vison

Radiochemistry group has been studying about radioactive isotopes produced in a high-energy accelerator facility by the radiochemical technique and the results have been used for the radiation safety control.


At the high-energy accelerator facility, accelerated particles sometimes hit the accelerator components and induce radionuclides by nuclear reactions. High-energy nuclear reactions are very complex and various kinds of radionuclides are produced. Induced radionuclides and their activity are depend on particle energy, beam power and target materials. We have been studying the mechanism of their production and their behavior in various materials on the various irradiation conditions by using radiochemical techniques effectively.

In order to release radioactive materials from the accelerator facility, careful evaluation of radioactivity is indispensable. Our group has contributed for the legislation of the handling of activated materials in the regulation rule in Japan and has been developing the measurement system for the radioactivity evaluation in accelerator components.

Radionuclides are also produced in air and cooling water of accelerator room. These nuclides form aerosols in air and colloids in water and their behaviors are very complex. Therefore, the understanding their chemical reaction is important for the safety control. We are studying radioactive aerosols and radio-colloids by sampling air and water from accelerator room during operation and by irradiating water and air samples at several accelerator facilities on various irradiation conditions. These results will be useful for the safety control at J-PARC.

Computer simulation has been used for safety design for accelerator facility. In case of high-intensity and high-energy accelerator, activation problem is also very important subject for computer simulation. In order to confirm the validity of calculation code, it is very important to obtain the experimental evidence on the typical condition. We develop an activation method and several radioactivity measurement techniques to depict the particle transportation, spatial distribution and energy spectrum indirectly. Our data have been used for the improvement of computer simulation code.