A proton synchrotron at the High Energy Accelerator Reserach Organization
(KEK) has been producing
12 GeV proton beam for users from Japan and abroad for the last 20 years.
During the operation, mixed radiation fields consisting of various radiations:
gamma-rays, neutron rays, and charged particles, are created and, after
the termination of operation,
the high radiation level due to gamma-rays is observed in the beam line tunnel.
In order to protect users and workers from these radiation, many safety
R & D projects must be conducted.
The radiochemistry group has been working on the following subjects from
the viewpoints of radio and nuclear chemistry including radiation physics
& chemistry and health physics: