Measurement of environmental radioactivity for RAON using HPGe detector and LSC

Abstract

The Rare isotope Accelerator complex for On-line experiments (RAON) has been built for providing the beam of exotic rare isotope of various energies at the Institute for Basic Science (IBS). The activation was evaluated by the MCNP simulation in the shielding design process, which guarantees the radiation safety on this facility. To ensure the additional radiation safety, the radiation is monitored inside and outside of the facility during operation of the RAON. The inside of the facility is monitored in real-time using the Radiation Monitoring System (RMS) composed of the various types of the detectors. In case of monitoring outside the facility, we measure the radioactivity of soil and groundwater around the facility. The soil is sampled in the five designated locations around the facility and the groundwater sample is taken from the seven collecting wells in the facility. We measure the radioactivities of ⁷Be, ²²Na, ⁵⁴Mn from the soil sample and those of ⁷Be, ²²Na, ³H from the groundwater sample. These radionuclides were chosen based on the MCNP simulation, which was compared with our measurement result.