Kunieda, Satoshi; Iwamoto, Osamu; Iwamoto, Nobuyuki; Minato, Futoshi; Okamoto, Tsutomu; Sato, Tatsuhiko; Nakashima, Hiroshi; Iwamoto, Yosuke; Iwamoto, Hiroki; Kitatani, Fumito; et al.
JAEA-Conf 2016-004, p.41 - 46, 2016/09
Neutron- and proton-induced cross-section data are required in a wide energy range beyond 20 MeV, for the design of accelerator applications. New evaluations are performed with recent knowledge in the optical and pre-equilibrium model calculations. We also evaluated cross-sections for p+Li and p+Be which have been highly requested from a medical field. The present high-energy nuclear data library, JENDL-4.0/HE, includes evaluated cross-sections for incident neutrons and protons up to 200 MeV (for about 130 nuclei). We overview substantial features of the library, i.e., (1) systematic evaluation with CCONE code, (2) challenges for evaluations of light nuclei and (3) inheritance of JENDL-4.0 and JENDL/HE-2007. In this talk, we also focus on the results of benchmark calculation for neutronics to show performance of the present library.
JAEA-Conf 2016-004, p.147 - 152, 2016/09
Copper is an important element relevant to heat sink material for fusion reactors, structural material for accelerator-driven systems, and so on. Therefore, more precise neutron nuclear data on copper isotopes are currently required. In addition, covariance data are also required to estimate uncertainties of various integral quantities obtained from calculation using the nuclear data. Covariance includes correlated uncertainties between different nuclear data, e.g. cross sections of different reactions. In evaluation on Cu of JENDL-4.0, the cross sections and angular distributions for several reactions were calculated by various computational codes. Towards preparation of covariance data, we evaluated neutron nuclear data on Cu by a consistent method using the CCONE code.
Furutachi, Naoya; Minato, Futoshi; Iwamoto, Osamu
JAEA-Conf 2016-004, p.93 - 98, 2016/09
To investigate feasibility of the nuclear transmutation of long-lived fission products (LLFPs), nuclear data used in the simulation calculation of transmutation system is essential. To improve the precision of simulation calculation, the nuclear data of various nuclei produced via nuclear transmutation of LLFPs involved in the simulation is also important. Since wide range of nuclei are expected to be produced depends on the method of transmutation, and there are no available experimental data for some of them, a systematic information based on a microscopic calculation is desirable. In this work, we have performed microscopic nuclear structure calculation to derive the structure parameters used in the nuclear data evaluation. We have calculated deformation parameters and ground-state spin and parities for Z = 30-55 medium nuclei including odd-even and odd-odd nuclei, expected to be produced via the transmutation of Se, Zr, Pd and Cs, using Hartree-Fock-Bogoliubov (HFB) theory. The calculation was done by HFBTHO code. The results are compared with the available experimental data, and reliability of the prediction with the present method is discussed.
JAEA-Conf 2016-004, p.141 - 146, 2016/09
This year we started a new activity for the next version of Japanese evaluated nuclear data library, JENDL-4.0. The next JENDL is planned to contribute to the transmutation of nuclear wastes. The evaluation activity will be focused on structural materials in the nuclear power plants, and the isomer production data will be supplemented to the library. In this work, we re-evaluated the nuclear data of Nb. We altered the resolved resonance parameters in the energy range between 2.6 and 7.0 keV. The agreement with experimental data was slightly improved in the average capture cross section. Cross sections above the RR region were re-calculated using the comprehensive nuclear data evaluation code CCONE. We adjusted the spin cutoff parameters of level densities to reproduce the measured isomer production ratios in the reactions , , , , and without spoiling the cross sections.
Shibata, Keiichi; Iwamoto, Nobuyuki; Kunieda, Satoshi; Minato, Futoshi; Iwamoto, Osamu
JAEA-Conf 2016-004, p.47 - 52, 2016/09
It is required to estimate radioactive products accurately for the decommissioning of LWRs. We have developed the neutron-induced activation cross-section file for this purpose. The products consist of 227 nuclides with half-lives larger than 30 days and 12 nuclides with very long half-lives. Target nuclei were selected by considering possible paths leading to the required products. The activation cross sections of these targets were taken from JENDL-4.0, JENDL/A-96 and the post JENDL-4.0 evaluations. As a result, we produced the activation cross-section file with 302 nuclides. Comparing with other evaluations, there exists a large difference especially for the capture cross sections leading to meta-stable states. The data will be released in FY2016 after achieving further improvements.
JAEA-Conf 2016-004, p.123 - 128, 2016/09
For the decommissioning of the Fukushima Daiichi Nuclear Power Station (1F), it is important to know the dose rate distribution in the primary containment vessel (PCV). However the distribution of radiation sources in PCV is not clear yet. There are three kinds of radiation sources in PCV. They are fuel debris, structures in PCV contaminated with Cs emitted at the 1F accident, and activated structures irradiated during normal reactor operating before the accident. In order to establish the evaluation method of the dose rate distribution in PCV, a preliminary calculation was carried out with JENDL-4.0. As a result, the sensitivity of each source to the dose distribution was obtained.
Iwamoto, Nobuyuki; Kosako, Kazuaki*; Murata, Toru*
JAEA-Conf 2016-004, p.53 - 58, 2016/09
Photonuclear data have been required to propose non-destructive assay and high energy -ray therapy as well as shielding design of an electron accelerator facility. A new photonuclear data file has been developed to take into account a wide variety of use. Nuclear data of stable light nuclides from Li to Ca were evaluated with experimental data and nuclear structural data. For nuclides above Ca, the photon absorption cross sections were calculated with GDR and QD model by nuclear reaction model codes, ALICE-F and CCONE. The incident photon energy covers the range up to 140 MeV. The data included absorption, particle production yield and nuclide production cross sections, and energy-angle differential cross sections of emitted particles. The new version has the nuclear data of 181 nuclides. In addition, an extended version is also planned to be released, in which systematic calculations by the ALICE-F code were performed for ~2500 nuclides other than those included in standard file.
Mizuyama, Kazuhito; Iwamoto, Nobuyuki; Iwamoto, Osamu
JAEA-Conf 2016-004, p.35 - 39, 2016/09
Improvement of the accuracy of neutron nuclear data for minor actinides (MAs) is required for the nuclear transmutation technique. The purpose of our study is development of evaluation method for improvement of nuclear data accuracy in MA isotopes. For the accurate evaluation, it is necessary to find out the reason of the discrepancy in previous data, to development of the accurate analysis method of the resonance parameters. So far, we found out the reason of the discrepancy of the thermal neutron capture cross section in previous measurements, and succeeded the correction. However the discrepancy of the resonance integral was not improved. The energy dependence of the epithermal neutron flux which has been used for the Cd ratio method can be different from the realistic experimental condition. This may be the reason for the discrepancy among the resonance integrals. For the accurate analysis of the resonance parameters, the precise resolution function's parameters are necessary. We are planning to obtain them by using the well-known stable nucleus and will apply them to the analysis of MAs.
Kono, Hiroshi*; Watanabe, Yukinobu*; Nakayama, Shinsuke; Iwamoto, Osamu; Ye, T.*; Ogata, Kazuyuki*
JAEA-Conf 2016-004, p.165 - 170, 2016/09
For engineering design of deuteron accelerator neutron sources, accurate nuclear data of deuteron-induced reactions on neutron converter (Li, Be, C, etc.) and accelerator structure material (Fe, Cr, Ni, etc.) are indispensable. Therefore we have developed a computational code system based on physics models dedicated for deuteron nuclear data evaluation. In the present study, we have analyzed the reactions on beryllium at incident deuteron energies up to 65 MeV. Since there is a lot of experimental Thick Target Neutron Yields (TTNYs), double-differential cross sections are calculated by the code system and then are converted to TTNYs. It is found that the calculated TTNYs reproduce the experimental ones fairly well except in the low neutron energy region.
Araki, Shohei*; Watanabe, Yukinobu*; Kitajima, Mizuki*; Sadamatsu, Hiroki*; Nakano, Keita*; Kin, Tadahiro*; Iwamoto, Yosuke; Satoh, Daiki; Hagiwara, Masayuki*; Yashima, Hiroshi*; et al.
JAEA-Conf 2016-004, p.159 - 164, 2016/09
Neutron production data from materials such as Li, Be and C bombarded by deuteron are required for design such as the facility of radiation damage for fusion materials and boron neutron capture therapy. However, there is little measurement of double differential neutron production cross sections (DDXs). Therefore, we have planned a series of DDXs measurements at incident energies more than 100 MeV in the Research Center for Nuclear Physics, Osaka University. The experiment was carried out with a carbon target at the neutron Time of Flight (TOF) course in RCNP. Emitted neutrons were detected by three different-size NE213 liquid organic scintillators (5.08 cm, 12.7 cm and 25.4 cm in dimeter and thickness) located at a distance of 7 m, 24 m and 74 m respectively. The neutron detection efficiencies of the detectors were calculated by SCINFUL-QMD code. It turned out that the calculation data fr carbon does not reproduce the experimental data satisfactorily well.
Iwamoto, Yosuke; Sato, Tatsuhiko; Niita, Koji*; Hashimoto, Shintaro; Ogawa, Tatsuhiko; Furuta, Takuya; Abe, Shinichiro; Kai, Takeshi; Matsuda, Norihiro; Iwase, Hiroshi*; et al.
JAEA-Conf 2016-004, p.63 - 69, 2016/09
A general purpose Monte Carlo Particle and Heavy Ion Transport code System, PHITS, is being developed through the collaboration of several institutes. PHITS can deal with the transport of nearly all particles, including neutrons, protons, heavy ions, photons, and electrons, over wide energy ranges using various nuclear reaction models and data libraries. PHITS users apply the code to various research and development fields such as nuclear technology, accelerator design, medical physics, and cosmic-ray research. This presentation briefly summarizes the physics models implemented in PHITS, and introduces some new models such as muon-induced nuclear reaction model and a de-excitation model EBITEM. We will also present the radiation damage cross sections for materials, PKA spectra and kerma factors calculated by PHITS under the IAEA-CRP activity titled "Primary radiation damage cross section."
Konno, Chikara; Kwon, Saerom; Ota, Masayuki; Sato, Satoshi
JAEA-Conf 2016-004, p.233 - 238, 2016/09
We compared the KERMA factors and DPA cross section data included in the official ACE and MATXS files of JENDL-4.0 with those of ENDF/B-VII.1 and JEFF-3.2. As a result, they were different from those of ENDF/B-VII.1 and JEFF-3.2 in a lot of nuclei, which was considered to be caused by the following new problems; (1) NJOY bugs, (2) huge helium production cross section data, (3) production data format in the nuclear data, (4) no detailed secondary particle data (energy-angular distribution data). The ACE and MATXS files of JENDL-4.0 with these problems should be revised based on this study.
Konno, Chikara; Kwon, Saerom; Ota, Masayuki; Sato, Satoshi
JAEA-Conf 2016-004, p.239 - 242, 2016/09
In order to specify reasons of the discrepancy between the calculated and measured results in analyses of benchmark experiments, some parts of some isotope data in nuclear data files are often modified and the modifies nuclear data files are processed with the NJOY code and the new ACE or MATXS files are used. However it is not easy to modify capture and elastic scattering data below 1 MeV with resonance data. Thus we devised a simple method to use capture and elastic scattering cross section data generated from resonance data with the NJOY code. This method was applied to detailed analyses of copper and molybdenum benchmark experiments at JAEA/FNS and it was demonstrated that this method was a very powerful tool.
Murata, Toru*; Kosako, Kazuaki*; Iwamoto, Nobuyuki
JAEA-Conf 2016-004, p.153 - 158, 2016/09
The experimental photo-nuclear data of H were measured by Faul et al. These data were analyzed with the same model as those applied to He photo-nuclear reactions to obtain production cross sections of neutron, proton and deuteron and also energy spectrum of these particles. Evaluated quantities will be contained in new Photo-nuclear Data File of JENDL. With these cross section of neutron production, feasibility study was made to reduce H density in the waste water by photon irradiation using an electron LINAC. Photon energy and angular distributions of bremsstrahlung were estimated using the method given by Hisdal, taking into account the multiple scattering of the incident electrons in the target. Preliminary results of photon energy spectrum at some emission angles and the H(,n)+(,2n) cross sections will be shown in the presentation. In case of irradiation of the waste water sample thickness of 50 cm with forward angle emission photon beam produced by 10mA electrons 100 sec., about a few percent reduction of H are expected with rough estimation.
Terada, Kazushi; Nakamura, Shoji; Kimura, Atsushi; Nakao, Taro; Harada, Hideo; Katabuchi, Tatsuya*; Igashira, Masayuki*; Hori, Junichi*
JAEA-Conf 2016-004, p.21 - 25, 2016/09
To obtain accurate cross section data, precise determination of the sample mass used in TOF measurements is essential, because uncertainties due to the sample mass are directly propagated to those of measured cross sections over the entire neutron energy region. Therefore, -ray emission probabilities of Am, Np and Pa have been precisely measured with gamma- and alpha-ray spectroscopic methods. The activities of the samples were determined by measuring alpha particles using a Si semiconductor detector. -rays emitted from the samples were measured with a planar type High-Purity Germanium (HPGe) detector. An efficiency curve of the Ge detector was derived by combining measured efficiencies and Monte Carlo simulation. The -ray emission probabilities for the major -rays of these nuclides were determined with uncertainties less than 2%.
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As a topic of Nuclear-data Tutorial, the author will make a lecture on the method to use nuclear-data covariance, which includes the background of nuclear-data covariance use, the physical meaning of covariance, the method to evaluate the prediction accuracy of nuclear core-parameters with covariance, and how to improve the nuclear design accuracy with covariance.