New JENDL-4.0/HE neutron and proton ACE files

Konno, Chikara

Journal of Nuclear Science and Technology, 6 Pages, 2023/00

https://doi.org/10.1080/00223131.2023.2237970

The JENDL-4.0/HE neutron and proton ACE files were produced in 2017 and those of 22 nuclei for neutron and 25 nuclei for proton were bundled in the PHITS code. Recently it was found that the following five data in the JENDL-4.0/HE neutron and proton ACE files had any problems; ACE files for N and O, heating numbers, damage energy production cross sections, secondary neutron multiplicities and fission cross sections. Thus new JENDL-4.0/HE neutron and proton ACE files were produced with the problems fixed. This paper describes the problems and how to produce the new neutron and proton ACE files in detail.

Monte Carlo simulations and n-p differential scattering data measured with Proton Recoil Telescopes

Terranova, N.*; Aberle, O.*; Alcayne, V.*; Kimura, Atsushi; 125 of others*

EPJ Web of Conferences, 239, p.01024_1 - 01024_5, 2020/09

https://doi.org/10.1051/epjconf/202023901024

Unified description of the fission probability for highly excited nuclei

Iwamoto, Hiroki; Meigo, Shinichiro

Journal of Nuclear Science and Technology, 56(2), p.160 - 171, 2019/02

https://doi.org/10.1080/00223131.2018.1539351

We present a new model to describe the fission probability of the high-energy fission model, as deduced from the intranuclear cascade calculation with the Intra-Nuclear Cascade model of Lige (INCL) version 4.6 and Prokofiev's phenomenological systematics of the proton-induced fission cross sections. This model is implemented in the de-excitation model of the Generalized Evaporation Model (GEM), and applied to Monte Carlo spallation reaction simulation using the Particle and Heavy Ion Transport code System (PHITS). Comparing with experimental data for subactinide nuclei shows that this model can provide a unified prediction of the proton-, neutron-, and deuteron-induced fission cross sections with markedly improved accuracy. The calculated fission fragments tend to shift to higher mass numbers. To account for the isotopic distributions of fission fragments within the framework of a coupled INCL/GEM, modification of INCL is required, especially for description of the highly-excited states of residual nuclei.

Research on neutron capture cross sections at J-PARC in ImPACT Project

Nakamura, Shoji; Kimura, Atsushi; Hales, B. P.; Iwamoto, Osamu; Tsubata, Yasuhiro; Matsumura, Tatsuro; Shibahara, Yuji*; Uehara, Akihiro*; Fujii, Toshiyuki*

JAEA-Conf 2017-001, p.15 - 22, 2018/01

https://doi.org/10.11484/jaea-conf-2017-001

Neutron nuclear data of long lived fission products (LLFPs) have been required as basic data for the technology of reduce environmental impact involved in high level radioactive wastes (HLW). The innovative large project called by "Impusing Paradigm Change through Disruptive Technologies Program: ImPACT" have been started from October, 2014. In the ImPACT project, some research groups of JAEA engaged in the Project No.2 (Nuclear Reaction Data Measurements), and have started measurements of neutron capture cross-section at J-PARC/MLF/ANNRI. In our research, we selected cesium-135 (Cs) nuclide (half life: 2.310 yr.) among LLFPs in the HLW, and decided to measure the neutron capture cross-sections of Cs. When measurement, the Cs sample might contained cecium-137 (Cs) as impurities because it's impossible to chemically separate each other. To measure the cross-sections of Cs, there should be also needed to know the cross-sections of Cs. In this work, sample maintenance also has been examined especially for selen-79 (Se) nuclide among LLFPs having difficulty in sample preparations. In this oral session, the outline of our research project will be presented together with a research motivation, situations of past reported data, total schedules, progress, future plans, and some of high light data for neutron capture cross-section measurements.

Estimation of covariance matrices for nuclear data of , and

Nakagawa, Tsuneo

Journal of Nuclear Science and Technology, 42(11), p.984 - 993, 2005/11

https://doi.org/10.3327/jnst.42.984

no abstracts in English

Validation of minor actinide cross sections by studying samples irradiated for 492 days at the dounreay prototype fast reactor, 2; Burnup calculations

Tsujimoto, Kazufumi; Kono, Nobuaki; Shinohara, Nobuo; Sakurai, Takeshi; Nakahara, Yoshinori; Mukaiyama, Takehiko; Raman, S.*

Nuclear Science and Engineering, 144(2), p.129 - 141, 2003/06

https://doi.org/10.13182/NSE03-A2348

To evaluate neutron cross-section data of minor actinides, separated actinide samples and dosimetry samples were irradiated at the Dounreay Prototype Fast Reactor for 492 effective full power days. Based on the burnup calculations of major actinide and dosimetry samples, the neutron flux distribution and the flux level were adjusted at the locations where minor actinide samples were irradiated. The burnup calculations were carried out for minor actinides using the determined flux distribution and flux level. This paper discusses the burnup calculations and the validation of minor actinide cross-section data in evaluated nuclear data libraries. We find that we can obtain reliable FIMA (fission per initial metallic atom) values by using the Nd method except that the uncertainties in the FIMA values are large for U, Pu, Am isotopes, and Cm isotopes because the Nd yields are known poorly for these isotopes and are probably overestimated. For these isotopes, measurements to improve the fission-yield data are needed. We also find that, in general, the JENDL-3.2 nuclear data for the minor actinides are adequate for the conceptual design study of transmutation systems. But, there are some nuclides (especially Pu and Pu) for which new measurements are needed particulary if the minor actinides constitute a major part of the nuclear fuel.

Nuclear data evaluation for Np, Am, Am and Am irradiated by neutrons and protons at energies up to 250 MeV

Konobeyev, A. Y.; Fukahori, Tokio; Iwamoto, Osamu

JAERI-Research 2002-032, 36 Pages, 2002/12

JAERI-Research-2002-032.pdf:1.33MB

The evaluation of nuclear data has been performed for Np, Am, Am and . Neutron data were obtained at the energies from 20 to 250 MeV and combined with JENDL-3.3 data at 20 MeV. Evaluation of the proton data has been done from 1 to 250 MeV. The coupled channel optical model was used to obtain angular distributions for elastic and inelastic scattering and transmission coefficients. Pre-equilibrium exciton model and Hauser-Feshbach statistical model were used to describe neutron and charged particles emission from the excited nuclei. These evaluation is the first work for producing the full set of evaluated file up to 250 MeV for Np and americium isotopes.

Neutron and proton nuclear data evaluation for U and U at energies up to 250 MeV

Konobeyev, A. Y.; Fukahori, Tokio; Iwamoto, Osamu

JAERI-Research 2002-028, 69 Pages, 2002/12

JAERI-Research-2002-028.pdf:1.93MB

Basic features of nuclear data evaluation for uranium isotopes U and 238U at intermediate energies are described. The coupled channel optical model was used to obtain total cross section, reaction cross section, angular distributions and transmission coefficients. The direct, pre-compound and evaporation models were used to describe neutron and charged particles emission from excited nuclei. The neutron data evaluated were combined with JENDL-3.3 data below 20 MeV to obtain a full data set in the whole energy range between 10 eV and 250 MeV. Evaluation of the proton data has been done at energies from 1 to 250 MeV

Comparison of (n,2n) and (n,3n) reaction cross sections for fission products in JENDL-3.2 with available experimental and other evaluated cross section data

Manokhin, V. N.*; Odano, Naoteru; Hasegawa, Akira

JAERI-Data/Code 2001-019, 169 Pages, 2001/07

JAERI-Data-Code-2001-019.pdf:5.26MB

Results of comparison of (n,2n) and (n,3n) reaction cross sections for 155 nuclei (Ge - Tb) in JENDL-3.2 with available experimental data, various evaluated data, and those estimated from systematics are summarized to assess validity of cross sections for threshold reactions for fission product nuclei in JENDL-3.2. Plots for comparisons are compiled and issues in cross section data in JENDL-3.2 are also discussed.

Evaluation of fission cross sections and covariances for U,U,U,Pu,Pu,and Pu

Kawano, Toshihiko*; Matsunobu, Hiroyuki*; Murata, Toru*; Zukeran, Atsushi*; Nakajima, Yutaka*; Kawai, Masayoshi*; Iwamoto, Osamu; Shibata, Keiichi; Nakagawa, Tsuneo; Osawa, Takaaki*; et al.

JAERI-Research 2000-004, p.76 - 0, 2000/02

JAERI-Research-2000-004.pdf:2.39MB

no abstracts in English