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JAEA Reports

Measurement of nuclide production cross-sections in high-energy proton-induced spallation reactions at J-PARC

Nakano, Keita; Matsuda, Hiroki*; Meigo, Shinichiro; Iwamoto, Hiroki; Takeshita, Hayato*; Maekawa, Fujio

JAEA-Research 2021-014, 25 Pages, 2022/03

JAEA-Research-2021-014.pdf:2.1MB

For the development of accelerator-driven transmutation system (ADS), measurement of nuclide production cross-sections in proton-induced reactions on $$^9$$Be, C, $$^{27}$$Al, $$^{45}$$Sc, and V have been performed. The measured data are compared with the calculations by the latest nuclear reaction models and with the nuclear data library to investigate the reproducibilities.

Journal Articles

Thermal-neutron capture cross-section measurement of tantalum-181 using graphite thermal column at KUR

Nakamura, Shoji; Shibahara, Yuji*; Endo, Shunsuke; Kimura, Atsushi

Journal of Nuclear Science and Technology, 58(10), p.1061 - 1070, 2021/10

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

In a well-thermalized neutron field, it is principally possible to drive a thermal-neutron capture cross-section without considering an epithermal neutron component. This was demonstrated by a neutron activation method using the graphite thermal column (TC-Pn) of the Kyoto University Research Reactor. First, in order to confirm that the graphite thermal column was a well-thermalized neutron field, neutron irradiation was performed with neutron flux monitors: $$^{197}$$Au, $$^{59}$$Co, $$^{45}$$Sc, $$^{63}$$Cu, and $$^{98}$$Mo. The TC-Pn was confirmed to be extremely thermalized on the basis of Westcott's convention, because the thermal-neutron flux component took a constant value regardless of the sensitivity of each flux monitor to epithermal neutrons. Next, as a demonstration, the thermal-neutron capture cross section of $$^{181}$$Ta(n,$$gamma$$)$$^{182m+g}$$Ta reaction was measured using the graphite thermal column, and then derived to be 20.5$$pm$$0.4 barn, which supported the evaluated value of 20.4$$pm$$0.3 barn. The $$^{181}$$Ta nuclide could be useful as a flux monitor that complements the sensitivity between $$^{197}$$Au and $$^{98}$$Mo monitors.

Journal Articles

Bias effects on g- and s-factors in Westcott convention

Harada, Hideo

Applied Sciences (Internet), 11(14), p.6558_1 - 6558_20, 2021/07

 Times Cited Count:0 Percentile:0(Chemistry, Multidisciplinary)

For accuracy improvement of neutron activation analysis and neutron capture cross section, bias effects are investigated on g- and s-factors in the Westcott convention. As origins of biases, a joining function shape, neutron temperature and sample temperature, have been investigated. Biases are quantitatively deduced for two 1/v isotopes ($$^{197}$$Au, $$^{59}$$Co) and six non-1/v isotopes ($$^{241}$$Am, $$^{151}$$Eu, $$^{103}$$Rh, $$^{115}$$In, $$^{177}$$Hf, $$^{226}$$Ra). The s-factor calculated with a joining function deduced recently by a detailed Monte Carlo simulation is compared to s-factors calculated with traditional joining functions by Westcott. The results show the bias induced by sample temperature is small as the order of 0.1% for g-factor and the order of 1% for s-factor. On the other hand, biases induced by a joining function shape for s-factor depend significantly on both isotopes and neutron temperature. As the result, reaction rates are also affected significantly as well. The bias size on reaction rate is given in the case of epithermal neutron index r = 0.1, for the eight isotopes.

Journal Articles

Thermal-neutron capture cross sections and resonance integrals of the $$^{243}$$Am(n,$$gamma$$)$$^{rm 244g}$$Am and $$^{243}$$Am(n,$$gamma$$)$$^{rm 244m+g}$$Am reactions

Nakamura, Shoji; Shibahara, Yuji*; Endo, Shunsuke; Kimura, Atsushi

Journal of Nuclear Science and Technology, 58(3), p.259 - 277, 2021/03

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

Research and development were made for accuracy improvement of neutron capture cross section data on $$^{243}$$Am among minor actinides. First, the emission probabilities of decay $$gamma$$ rays were obtained with high accuracy, and the amount of the ground state of $$^{244}$$Am produced by reactor neutron irradiation of $$^{243}$$Am was examined by $$gamma$$-ray measurement. Next, the total amount of isomer and ground states was examined by $$alpha$$-ray measurement. Thermal-neutron capture cross sections and resonance integrals were derived both for the $$^{243}$$Am(n,$$gamma$$)$$^{rm 244g}$$Am and for $$^{243}$$Am(n,$$gamma$$)$$^{rm 244m+g}$$Am reactions.

Journal Articles

Measurement of nuclide production cross section for lead and bismuth with proton in energy range from 0.4 GeV to 3.0 GeV

Matsuda, Hiroki; Meigo, Shinichiro; Iwamoto, Hiroki; Maekawa, Fujio

EPJ Web of Conferences, 239, p.06004_1 - 06004_4, 2020/09

 Times Cited Count:0 Percentile:0.19

For the Accelerator-Driven nuclear transmutation System (ADS), nuclide production yield estimation in the lead-bismuth target is important to manage the target. However, experimental data of nuclide production yield by spallation and high-energy fission reactions are scarce. In order to obtain the experimental data, we experimented in J-PARC using $$^{mathrm{nat}}$$Pb and $$^{mathrm{209}}$$Bi samples. The samples were irradiated with protons at various kinematic energy points between 0.4 and 3.0 GeV. After the irradiation, the nuclide production cross section over $$^{mathrm{7}}$$Be to $$^{mathrm{183}}$$Re was obtained by spectroscopic measurement of decay gamma-rays from the samples with HPGe detectors. The present experimental results were compared with the evaluated data (JENDL-HE/2007) and the calculation with the PHITS code and the INCL++ code. The present experiment data showed consistency with other experimental data with better accuracy than other ones. In reactions to produce light nuclides, JENDL and calculation with the PHITS and INCL++ for $$^{mathrm{7}}$$Be production agreed with the data.$$^{mathrm{22}}$$Na production, however, underestimated about 1/10 times. For middle to heavy nuclide productions cases, both calculations agreed with the experiment by a factor of two. JENDL showed lower energy having a maximum value of excitation function maximal value than the experimental data.

Journal Articles

Measurement for thermal neutron capture cross sections and resonance integrals of the $$^{243}$$Am(n,$$gamma$$)$$^{rm 244g}$$Am, $$^{rm 244m+g}$$Am reactions

Nakamura, Shoji; Endo, Shunsuke; Kimura, Atsushi; Shibahara, Yuji*

KURNS Progress Report 2019, P. 132, 2020/08

Research and development were made for accuracy improvement of neutron capture cross section data on $$^{243}$$Am among minor actinides. First, the emission probabilities of decay $$gamma$$ rays were obtained with high accuracy, and the amount of the ground state of $$^{244}$$Am produced by reactor neutron irradiation of $$^{243}$$Am was examinded by $$gamma$$-ray measurement. Next, the total amount of isomer and ground states was examoned by $$alpha$$-ray measurement.

Journal Articles

Measurements of thermal-neutron capture cross-section of cesium-135 by applying mass spectrometry

Nakamura, Shoji; Shibahara, Yuji*; Kimura, Atsushi; Iwamoto, Osamu; Uehara, Akihiro*; Fujii, Toshiyuki*

Journal of Nuclear Science and Technology, 57(4), p.388 - 400, 2020/04

 Times Cited Count:1 Percentile:23.13(Nuclear Science & Technology)

The thermal-neutron capture cross-section ($$sigma_{0}$$) and resonance integral(I$$_{0}$$) were measured for the $$^{135}$$Cs(n,$$gamma$$)$$^{136}$$Cs reaction by an activation method and mass spectrometry. We used $$^{135}$$Cs contained as an impurity in a normally available $$^{137}$$Cs standard solution. An isotope ratio of $$^{135}$$Cs and $$^{137}$$Cs in a standard $$^{137}$$Cs solution was measured by mass spectrometry to quantify $$^{135}$$Cs. The analyzed $$^{137}$$Cs samples were irradiated at the hydraulic conveyer of the research reactor in Institute for Integral Radiation and Nuclear Science, Kyoto University. Wires of Co/Al and Au/Al alloys were used as neutron monitors to measure thermal-neutron fluxes and epi-thermal Westcott's indices at an irradiation position. A gadolinium filter was used to measure the $$sigma_{0}$$, and a value of 0.133 eV was taken as the cut-off energy. Gamma-ray spectroscopy was used to measure induced activities of $$^{137}$$Cs, $$^{136}$$Cs and monitor wires. On the basis of Westcott's convention, the $$sigma_{0}$$ and I$$_{0}$$ values were derived as 8.57$$pm$$0.25 barn, and 45.3$$pm$$3.2 barn, respectively. The $$sigma_{0}$$ obtained in the present study agreed within the limits of uncertainties with the past reported value of 8.3$$pm$$0.3 barn.

Journal Articles

Activation measurement for thermal-neutron capture cross-section of Cesium-135

Nakamura, Shoji; Kimura, Atsushi; Iwamoto, Osamu; Shibahara, Yuji*; Uehara, Akihiro*; Fujii, Toshiyuki*

KURNS Progress Report 2018, P. 106, 2019/08

Under the ImPACT project, the neutron capture cross-section measurements of Cesium-135 ($$^{135}$$Cs) among the long-lived fission products have been performed at Kyoto University. This paper reports measurements of the thermal-neutron capture cross-section of $$^{135}$$Cs at the Kyoto University Research Reactor (KUR).

Journal Articles

Measurements of thermal-neutron capture cross-section and resonance integral of neptunium-237

Nakamura, Shoji; Kitatani, Fumito; Kimura, Atsushi; Uehara, Akihiro*; Fujii, Toshiyuki*

Journal of Nuclear Science and Technology, 56(6), p.493 - 502, 2019/06

 Times Cited Count:3 Percentile:57.07(Nuclear Science & Technology)

The thermal-neutron capture cross-section($$sigma_{0}$$)and resonance integral(I$$_{0}$$) were measured for the $$^{237}$$Np(n,$$gamma$$)$$^{238}$$Np reaction by an activation method. A method with a Gadolinium filter, which is similar to the Cadmium difference method, was used to measure the $$sigma_{0}$$ with paying attention to the first resonance at 0.489 eV of $$^{237}$$Np, and a value of 0.133 eV was taken as a cut-off energy. Neptunium-237 samples were irradiated at the pneumatic tube of the Kyoto University Research Reactor in Institute for Integral Radiation and Nuclear Science, Kyoto University. Wires of Co/Al and Au/Al alloys were used as monitors to determine thermal-neutron fluxes and epi-thermal Westcott's indices at an irradiation position. A $$gamma$$-ray spectroscopy was used to measure activities of $$^{237}$$Np, $$^{238}$$Np and neutron monitors. On the basis of Westcott's convention, the $$sigma_{0}$$ and I$$_{0}$$ values were derived as 186.9$$pm$$6.2 barn, and 1009$$pm$$90 barn, respectively.

Journal Articles

Proton-induced activation cross section measurement for aluminum with proton energy range from 0.4 to 3 GeV at J-PARC

Matsuda, Hiroki; Meigo, Shinichiro; Iwamoto, Hiroki

Journal of Nuclear Science and Technology, 55(8), p.955 - 961, 2018/08

 Times Cited Count:1 Percentile:17.98(Nuclear Science & Technology)

We have started an experimental program to measure activation cross sections systematically in the proton-induced spallation reaction in structural materials commonly used in high-intensity proton accelerator-based facilities, such as Japan Proton Accelerator Research Complex (J-PARC). As the first step of the program, aluminum (Al) was chosen to verify the adequacy of the measurement technique implemented in a J-PARC proton beam environment because data of Al have been relatively well studied both by experimental measurement and simulation. Activation cross sections of $$^{7}$$Be, $$^{22}$$Na, and $$^{24}$$Na in Al were measured at proton energy points from 0.4, 1.3, 2.2 to 3.0 GeV, which could be delivered smoothly from the synchrotron. The validity of experimental data has been verified by introducing an effective proton numbers determination procedure. We compared the measured data with existing experimental data, the evaluated data (JENDL-HE/2007), and the calculations with several intra-nuclear cascade models by the Particle and Heavy Ion Transport code System (PHITS) code. Although the experimental data agreed with JENDL-HE/2007, the calculations underestimated about 40%. This could come from the evaporation model (generalized evaporation model) being implemented in the PHITS code. We found that the calculations agreed with the experimental data by an upgraded PHITS code.

Journal Articles

Activation measurements of neputunium-237 at KURRI-Linac

Nakamura, Shoji; Terada, Kazushi; Shibahara, Yuji*; Uehara, Akihiro*; Fujii, Toshiyuki*; Sano, Tadafumi*; Takahashi, Yoshiyuki*; Hori, Junichi*

KURRI Progress Report 2015, P. 67, 2016/08

The activation measurements of Np-237 were performed with neutron sources at KURRI-Linac. It was found that activation measurements supported the evaluated cross-section data of JENDL-4.0.

Journal Articles

Measurements of americium isotopes by activation method at KURRI-Linac

Nakamura, Shoji; Terada, Kazushi; Takahashi, Yoshiyuki*; Sano, Tadafumi*; Hori, Junichi*

KURRI Progress Report 2015, P. 69, 2016/08

Neutron capture cross section measurements has been conducted for Minor Actinides (MAs) under the research project entitled by "Research and development for Accuracy Improvement of neutron nuclear data on Minor ACtinides (AIMAC)". The present work selected two americium isotopes, $$^{241}$$Am and $$^{243}$$Am, were selected, and measurements were carried out by an activation method with neutron sources at KURRI-Linac. It was found that the neutron flux at the target positon was of the order of 10$$^{8}$$ (n/cm$$^{2}$$s). The reaction rates of $$^{241}$$Am and $$^{243}$$Am were obtained by $$alpha$$- and $$gamma$$-ray measurements of the irradiated Am samples.

Journal Articles

Development of multi-group neutron activation cross-section library for decommissioning of nuclear facilities

Okumura, Keisuke; Kojima, Kensuke; Tanaka, Kenichi*

JAEA-Conf 2015-003, p.43 - 47, 2016/03

In the safety assessment concerning disposal of radioactive wastes generated in the decommissioning of nuclear facilities, it is necessary to evaluate the radionuclide inventory produced by the activation of structured materials. For this purpose, we have to pay much attention to the activation of many impurities irradiated in various neutron spectra depending on their positions and materials. Therefore, accurate activation cross-section data are necessary for many nuclides and reactions. A new multi-group neutron activation cross-section library (MAXS) was developed based on the recent nuclear data JENDL-4.0 and JEFF-3.0/A to apply it to the activation calculations for the decommissioning of nuclear facilities. The library contains cross-sections and isomeric ratios for many reactions such as (n,$$gamma$$), (n,f), (n,2n), (n,3n), (n,p), (n,$$alpha$$), (n,d), (n,t), (n,n$$alpha$$), (n,np), and so on, for 779 nuclides, in the 199-energy group structure of VITAMIN-B6.

Journal Articles

Measurements of deuteron-induced activation cross sections for IFMIF accelerator structural materials in the energy range of 22-40 MeV

Ochiai, Kentaro; Nakao, Makoto*; Hori, Junichi*; Sato, Satoshi; Yamauchi, Michinori*; Ishioka, Noriko; Nishitani, Takeo

Fusion Engineering and Design, 81(8-14), p.1459 - 1464, 2006/02

 Times Cited Count:2 Percentile:18.25(Nuclear Science & Technology)

The IFMIF consists of two 40 MeV deuteron linear accelerators with 125 mA beam current each. The structure materials of the accelerators are activated with high energetic deuteron. To measure the activation cross sections with $$^{27}$$Al, $$^{rm nat}$$Cu, $$^{rm nat}$$W, $$^{rm nat}$$V, $$^{rm nat}$$Ni, $$^{rm nat}$$Fe, and $$^{rm nat}$$Ta samples irradiated with 22-40 MeV deuteron beams, we have carried out the irradiation experiment of the main elements of the IFMIF candidate materials by using the deutron beam of the AVF cyclotron of the TIARA facility in JAERI/Takasaki.

Journal Articles

Measurements of deuteron-induced activation cross sections for IFMIF accelerator structural materials

Nakao, Makoto*; Hori, Junichi*; Ochiai, Kentaro; Sato, Satoshi; Yamauchi, Michinori*; Ishioka, Noriko; Nishitani, Takeo

Proceedings of International Conference on Nuclear Data for Science and Technology (ND 2004), p.1489 - 1492, 2004/09

no abstracts in English

JAEA Reports

DCHAIN-SP 2001: High energy particle induced radioactivity calculation code

Kai, Tetsuya; Maekawa, Fujio; Kosako, Kazuaki*; Kasugai, Yoshimi; Takada, Hiroshi; Ikeda, Yujiro

JAERI-Data/Code 2001-016, 82 Pages, 2001/03

JAERI-Data-Code-2001-016.pdf:4.22MB

no abstracts in English

Journal Articles

Experimental validation of decay heat calculation codes and associated nuclear data libraries for fusion energy

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

Journal of Nuclear Science and Technology, 38(1), p.53 - 62, 2001/01

no abstracts in English

Journal Articles

Production of a dosimetry cross section set up to 50MeV

Maekawa, Fujio; Von-Moellendorff, U.*; Wilson, P. P. H.*; Wada, Masayuki*; Ikeda, Yujiro

Reactor Dosimetry: Radiation Metrology and Assessment (ASTM STP 1398), p.417 - 424, 2001/00

no abstracts in English

Journal Articles

Experimental study on beryllium-7 production via sequential reactions in lithium-containing compounds irradiated by 14-MeV neutrons

Maekawa, Fujio; Verzilov, Y.M.*; Smith, D. L.*; Ikeda, Yujiro

Journal of Nuclear Materials, 283-287(Part.2), p.1448 - 1452, 2000/12

 Times Cited Count:5 Percentile:38.85(Materials Science, Multidisciplinary)

no abstracts in English

Journal Articles

The IRAC code system to calculate activation and transmutation in the TIARA Facility

Tanaka, Susumu; Fukuda, Mitsuhiro; Nishimura, Koichi; Hosono, Masakazu; Watanabe, Hiromasa; Yamano, Naoki*

Journal of Nuclear Science and Technology, 37(Suppl.1), p.840 - 844, 2000/03

no abstracts in English

31 (Records 1-20 displayed on this page)