Evaluation of radiation dose caused by bremsstrahlung photons generated by high-energy beta rays using the PHITS and GEANT4 simulation codes

Shikaze, Yoshiaki

Journal of Nuclear Science and Technology, 61(7), p.894 - 910, 2024/07

https://doi.org/10.1080/00223131.2023.2285934

Among the radioactive nuclides inside the nuclear reactor buildings emitted by the Fukushima Daiichi nuclear reactor accident, high-energy beta-ray sources, such as strontium-90 and yttrium-90, generate bremsstrahlung photons in the building materials, comprising the wall, floor, and interior structure. Therefore, evaluating the radiation dose of the bremsstrahlung to the workers in the nuclear reactor building is crucial for radiation protection. The precision of the evaluation calculation of the bremsstrahlung dose was investigated by comparing the Particle and Heavy Ion Transport code System (PHITS) and the GEometry ANd Tracking (GEANT4) simulation code results. In the calculation, behind various shielding plates (lead, copper, aluminum, glass, and polyethylene, with thicknesses ranging from 1.0 to 40 mm), the water cylinder was set as the evaluated material, the absorbed dose and the deposited energy spectrum by the bremsstrahlung photons were obtained, and the characteristics and differences for both simulation codes were investigated. In the comparison results of the deposited energy spectrum, the spectral shapes have consistent trends. In the energy range below several tens of keV, a peak is seen in the PHITS spectrum for the lead shielding material. In comparing the absorbed dose under various conditions of the shielding plate for generating bremsstrahlung photons, most results for both codes correlate within an 10% difference for 2.280 MeV beta-ray sources and an 20% difference for 0.5459 MeV beta-ray sources, except for 30% for 20 mm thick lead. Although there were differences in some cases, the evaluation results of the two simulation codes were concluded to correlate well with the above precision.

Evaluation of energy spectrum around structural materials in radiation environments

Matsumura, Taichi; Nagaishi, Ryuji; Katakura, Junichi*; Suzuki, Masahide*

Radiation Physics and Chemistry, 166, p.108493_1 - 108493_9, 2020/01

https://doi.org/10.1016/j.radphyschem.2019.108493

In this work, when radiation sources of Cs, Sr and Y were assumed to be put in the front of a plain SUS304 plate as a typical material submerged in water, energy spectra of secondary photons and electrons at the front and back sides of plate were simulated with changing the thickness of plate, and spacing between the source and plate by using a Monte Carlo calculation code of PHITS. In the case of Cs gamma-ray (monochromatic 662 keV), the energy spectra at the front side was smaller than those at the back side due to the existence of plate. Then the dependence of spectra on the plate thickness was observed more clearly at the back side than at the front side. It was clearly shown how the energy spectra of photons and electrons varied with the incident radiation type, the spacing, and the thickness.

Scaling of the energy confinement time with and collisionality approaching ITER conditions

Cordey, J. G.*; Thomsen, K.*; Chudnovskiy, A.*; Kardaun, O. J. W. F.*; Takizuka, Tomonori; Snipes, J. A.*; Greenwald, M.*; Sugiyama, L.*; Ryter, F.*; Kus, A.*; et al.

Nuclear Fusion, 45(9), p.1078 - 1084, 2005/09

https://doi.org/10.1088/0029-5515/45/9/007

The condition of the latest version of the ELMy H-mode database has been re-examined. It is shown that there is bias in the ordinary least squares regression for some of the variables. To address these shortcomings three different techniques are employed: (a)principal component regression, (b)an error in variables technique and (c)the selection of a better conditioned dataset with fewer variables. Scalings in terms of the dimensionless physics valiables, as well as the standard set of engineering variables, are derived. The new scalings give a very similar performance for existing scalings for ITER at the standard beta, but a much improvement performance at higher beta.

Development of whole energy absorption spectrometer for decay heat measurement

Maekawa, Fujio; Wada, Masayuki*; Ikeda, Yujiro

Nuclear Instruments and Methods in Physics Research A, 450(2-3), p.467 - 478, 2000/08

https://doi.org/10.1016/S0168-9002(00)00301-6

no abstracts in English

Energy systematics of low-lying O states in neutron-deficient Ba nuclei

Asai, Masato*; Sekine, Toshiaki; Osa, Akihiko; Koizumi, Mitsuo; Kojima, Yasuaki*; Shibata, M.*; ; Kawade, Kiyoshi*

Physical Review C, 56(6), p.3045 - 3053, 1997/12

https://doi.org/10.1103/PhysRevC.56.3045

no abstracts in English

Whole energy absorption spectrometer for decay heat measurement of fusion reactor materials and application for beta-ray spectrum measurement

Maekawa, Fujio; Ikeda, Yujiro

Proc. of Int. Conf. on Nucl. Data for Science and Technol., 59, p.1201 - 1205, 1997/00

no abstracts in English

decay of unstable praseodymium isotopes: Pr, Pr and the new isotope Pr

Osa, Akihiko; Asai, Masato*; Koizumi, Mitsuo; Sekine, Toshiaki; ; ; Yamamoto, Hiroshi*; Kawade, Kiyoshi*

Nuclear Physics A, 588, p.185C - 190C, 1995/00

https://doi.org/10.1016/0375-9474(95)00137-P

no abstracts in English

Operational scenarios to avoid disruptions in JT-60U

Yoshino, Ryuji; Neyatani, Yuzuru; Isei, Nobuaki; Matsukawa, Makoto; Hosogane, Nobuyuki

Purazuma, Kaku Yugo Gakkai-Shi, 70(10), p.1081 - 1101, 1994/10

http://ci.nii.ac.jp/naid/110003825883

no abstracts in English

Rise time spectra of and () rays from solid and solution sources with several solid scintillators

Usuda, Shigekazu; Mihara, Akira; Abe, Hitoshi

Nuclear Instruments and Methods in Physics Research A, 321, p.247 - 253, 1992/00

https://doi.org/10.1016/0168-9002(92)90396-L

no abstracts in English

Reevaluation of decay energies of fission product nuclides in JNDC FP decay data file

;

JAERI-M 86-041, 23 Pages, 1986/03

JAERI-M-86-041.pdf:0.6MB

no abstracts in English