Hee-Seock Lee

A new method of dose calculation algorithm, called GPU-accelerated Monte Carlo and collapsed cone Convolution (GMCC) was developed to improve the calculation speed of BNCT treatment planning system. The GPU-accelerated Monte Carlo routine in GMCC is used to simulate the neutron transport over whole energy range and the Collapsed Cone Convolution method is to calculate the gamma dose. Other dose components due to alpha particles and protons, are calculated using the calculated neutron flux and re

Differential photoneutron yields produced from Al, Ti, Cu, Sn, W, and Pb targets by an irradiation of 2.04 GeV electrons were measured at the angle of 90° relative to the incident beam. The neutron energy range measured in this experiments was between 10 and 400 MeV. The systematics of the yields was studied for two target conditions : a target element and a target thickness. The neutron productions by a photonuclear reaction and by a hadron cascade due to secondary particles were considered to

A study of differential photo-neutron yields by irradiation with 2 GeV electrons has been carried out. In this extension of a previous study in which measurements were made at an angle of 90 degrees relative to incident electrons, the differential photo-neutron yield was obtained at two other angles, 48 degrees and 140 degrees, to study its angular characteristics. Photo-neutron spectra were measured using a pulsed beam time-of-flight method and a BC418 plastic scintillator. The reliable range o

The linear accelerator of the Rare Isotope Science Project (RISP) accelerates 200 MeV/nucleon 238 U ions in a multi-charge states. Many kinds of radiations are generated while the primary beam is transported along the beam line. The stripping process using thin carbon foil leads to complicated radiation environments at the 90-degree bending section. The charge distribution of 238 U ions after the carbon charge stripper was calculated by using the LISE++ program. The estimates of the radiation en

A skyshine is the dominant component of the prompt radiation at off-site. Several experimental studies have been done to estimate the neutron skyshine at a few accelerator facilities. In this work, the neutron transports from a source place to off-site location were simulated using the Monte Carlo codes, FLUKA and PHITS. The transport paths were classified as skyshine, direct (transport), groundshine and multiple-shine to understand the contribution of each path and to develop a general evaluati

The study of differential photo-neutron yields by the irradiation of 2 GeV electrons has been carried out. In this extended study of previous measurements, which were done at the angle of 90° relative to incident electrons, the differential photo-neutron yield was obtained at two other angles of 48° and 140° to study its angular characteristics. The experimental setup was improved to reduce huge photon backgrounds in a linear accelerator tunnel. Photo-neutron spectra were measured using a pulsed

A PAL-XFEL is a free electron laser using 10-GeV, 0.2-nC electron beams. The failure of the main dump magnet can cause a serious radiation risk because electron beams go straight to the experimental area of the hard X-ray beamlines and high-energy radiation is produced in the forward direction. This type of accident should be prevented through a suitable shielding design and a Personal Safety and Interlock System. A proper safety design based on a reliable method for estimating the radiation dos

During the decommissioning of nuclear and particle accelerator facilities, a considerable amount of large-scale radioactive waste may be generated. Accurately defining the activation level of the waste is crucial for proper disposal. However, directly measuring the internal radioactivity distribution poses challenges. This study introduced a novel technology employing machine learning to assess the internal radioactivity distribution based on external measurements. Random radioactivity distribut