JOPSS - Search Results

Journal Articles

Cross-section-induced uncertainty evaluation of MA sample irradiation test calculations with consideration of dosimeter data

Sugino, Kazuteru; Numata, Kazuyuki*; Ishikawa, Makoto; Takeda, Toshikazu*

Annals of Nuclear Energy, 130, p.118 - 123, 2019/08

https://doi.org/10.1016/j.anucene.2019.02.035

Times Cited Count：0 Percentile：0.01(Nuclear Science & Technology)

In MA sample irradiation test data calculations, the neutron fluence during irradiation period is generally scaled by using dosimetry data in order to improve calculation accuracy. In such a case, appropriate correction is required to burnup sensitivity coefficients obtained by the conventional generalized perturbation theory because some cancellations occur in the burnup sensitivity coefficients. Therefore, a new formula for the burnup sensitivity coefficient has been derived with the consideration of the neutron fluence scaling effect (NFS). In addition, the cross-section-induced uncertainty is evaluated by using the obtained burnup sensitivity coefficients and the covariance data based on the JENDL-4.0.

Journal Articles

Sensitivity and uncertainty analysis of $beta_{rm eff}$ for MYRRHA using a Monte Carlo technique

Iwamoto, Hiroki; Stankovskiy, A.*; Fiorito, L.*; Van den Eynde, G.*

EPJ Nuclear Sciences & Technologies (Internet), 4, p.42_1 - 42_7, 2018/11

https://doi.org/10.1051/epjn/2018023

This paper presents a nuclear data sensitivity and uncertainty analysis of the effective delayed neutron fraction $beta_{rm eff}$ for critical and subcritical cores of the MYRRHA reactor using the continuous-energy Monte Carlo transport code MCNP. The $beta_{rm eff}$ sensitivities are calculated by the modified -ratio method proposed by Chiba. Comparing the $beta_{rm eff}$ sensitivities obtained with different scaling factors introduced by Chiba shows that a value of is the most suitable for the uncertainty quantification of $beta_{rm eff}$ . Using the calculated $beta_{rm eff}$ sensitivities and the JENDL-4.0u covariance data, the $beta_{rm eff}$ uncertainties for the critical and subcritical cores are determined to be 2.2 0.2% and 2.0 0.2%, respectively, which are dominated by delayed neutron yield of $^{239}$ Pu and $^{238}$ U.

JAEA Reports

Characteristics of 64 64 channel high-position resolution neutron imaging detector

Sakasai, Kaoru; Katagiri, Masaki; Matsubayashi, Masahito; Rhodes, N.*; Schoonveld, E.*

JAERI-Research 2004-020, 19 Pages, 2004/12

JAERI-Research-2004-020.pdf:4.57MB

no abstracts in English

JAEA Reports

Neutron image characteristics of imaging plates using SrBPO $_{5}$ :Eu $^{2+}$ photostimulabe phosphors

Sakasai, Kaoru; Katagiri, Masaki; Nakamura, Tatsuya

JAERI-Research 2004-019, 33 Pages, 2004/12

JAERI-Research-2004-019.pdf:7.99MB

As a new candidate for raw materials of a neutron imaging plate, characteristics of a SrBPO $_{5}$ :Eu $^{2+}$ phosphor that has boron (B) in the base matrix as a neutron converter have been investigated. The phosphor has a strong merit that it generates photostimulated luminescence of 390 nm by illumination of red laser light after neutron irradiation. The emission and excitation wavelengths were the same as those of commercially available neutron imaging plate. Therefore, the authors have fabricated neutron imaging plates by painting the phosphor on Al plates. Neutron imaging experiments using the fabricated imaging plates were carried out with a commercially available image reader. A Li block was used as a camera subject in the experiments. As a result of the experiments, it was confirmed that the neutron image was clearly obtained, though the intensity of the image was not so high. The position resolution of 0.2 mm was obtained when the readout resolution of 50 m in the reader was used.

Journal Articles

Effects of neutron irradiation on some superplastic characteristics of tetragonal zirconia polycrystals containing 3 mol% yttria

Shibata, Taiju; Ishihara, Masahiro; Motohashi, Yoshinobu*; Ito, Tsutomu*; Baba, Shinichi; Kikuchi, Makoto*

Materials Transactions, 45(8), p.2580 - 2583, 2004/08

https://doi.org/10.2320/matertrans.45.2580

Times Cited Count：3 Percentile：26.84(Materials Science, Multidisciplinary)

Fast neutrons (energy 1.610 $^{23}$ J) were irradiated to tetragonal zirconia polycrystals containing 3 mol% yttria (3Y-TZP) at the fluence levels of 2.510 $^{24}$ (Light irradiation) and 4.310 $^{24}$ (Heavy irradiation) m $^{-2}$ . The irradiation caused no significant swelling in the 3Y-TZP specimens. After the neutron irradiation, superplastic characteristics were examined by tensile tests at a temperature range from 1623 to 1773 K with initial strain rates ranging from 5.010 $^{-4}$ to 1.6710 $^{-2}$ s $^{-1}$ . It was found that the elongation to fracture of the irradiated specimens was quite small in comparison with the unirradiated ones. The apparent activation energy for the superplastic flow of the irradiated 3Y-TZP was fairly high, i.e., 781 and 693 kJ・mol $^{-1}$ for Light and Heavy irradiations, respectively. Atomic displacement damages and defects in the 3Y-TZP caused by the irradiation were thought to be main causes of these property changes.