JOPSS - Search Results

Journal Articles

Measurements of neutron total and capture cross sections of $^{139}$ La and evaluation of resonance parameters

Endo, Shunsuke; Kawamura, Shiori*; Okudaira, Takuya*; Yoshikawa, Hiromoto*; Rovira Leveroni, G.; Kimura, Atsushi; Nakamura, Shoji; Iwamoto, Osamu; Iwamoto, Nobuyuki

European Physical Journal A, 59(12), p.288_1 - 288_12, 2023/12

https://doi.org/10.1140/epja/s10050-023-01203-4

Times Cited Count：0 Percentile：0.02(Physics, Nuclear)

no abstracts in English

Journal Articles

Evaluation of neutron resonance parameters for Zr isotopes

Ichihara, Akira

JAEA-Conf 2017-001, p.103 - 108, 2018/01

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

In the Nuclear Data Center of Japan Atomic Energy Agency (JAEA-NDC), we are engaged in the evaluation activity for the next version of the Japanese Evaluated Nuclear Data Library, JENDL-4.0. Zirconium is an important structural material in nuclear reactors, and zircaloys are being employed in fuel rods. Also, $^{93}$ Zr is a long-lived fission product (LLFP) with a half-life of 1.6110 $^{6}$ years. At present we are investigating resonance parameters of Zr isotopes using experimental data published after the evaluation of JENDL-4.0. Through this work, a negative resonance of $^{93}$ Zr in JENDL-4.0 was removed to reproduce the J-PARC/MLF/ANRRI experiment. The resonance parameters for other natural Zr isotopes will be altered by adopting the data obtained at CERN n-TOF experiments.

Journal Articles

Neutron resonance spectroscopy for the characterization of materials and objects

Schillebeeckx, P.*; Becker, B.*; Harada, Hideo; Kopecky, S.*

Landolt-Brnstein Group 1, Vol.26; Numerical Data and Functional Relationships in Science and Technology, Subv.A; Neutron Resonance Parameters, p.4 - 52, 2015/00

The probability that neutrons interact with nuclei strongly depends on the energy of the incoming neutron. There are resonances at specific energies for each nuclide.Since resonances appear at energies that are specific for each nuclide, they can be used to determine the elemental and in some cases even the isotopic composition of materials and objects. The resonance structures in total and capture cross sections are the basis of Neutron Resonance Transmission Analysis (NRTA) and Neutron Resonance Capture Analysis (NRCA), respectively. Principles of NRTA and NRCA are reviewed. Neutron Resonance Densitometry (NRD) combining NRTA and NTCA is also reviewed as a non-destructive method to characterize particle-like debris of melted fuel.

JAEA Reports

Criticality and doppler reactivity worth uncertainty due to resolved resonance parameter errors; Formula for sensitivity analysis

Zukeran, Atsushi*; Nakagawa, Tsuneo; Shibata, Keiichi; Ishikawa, Makoto*; Hino, Tetsushi*

JAERI-Research 2004-026, 102 Pages, 2005/02

JAERI-Research-2004-026.pdf:7.68MB

Reactivity uncertainties such as effective multiplication factor can be estimated by the sensitivity coefficients of the infinitely diluted cross section and resonance self-shielding factor to the changes of resonance parameters of interest. In the present work, the uncertainties of the resolved resonance parameters for the evaluated nuclear data file JENDL-3.2 were estimated on the basis of Breit-Wigner Multi-level formula. The resonance self-shielding factor based on NR-approximation is analytically described. Reactivity uncertainty evaluation method for the effective multiplication factor k $_{eff}$ , temperature coefficient , and Doppler reactivity worth is developed by means of the sensitivity coefficient against the resonance parameter. Final uncertainties are estimated by means of error propagation law using the level-wise uncertainties. Preliminary uncertainty of Doppler reactivity worth results about 4% at the temperature 728 K for large sodium-cooled FBR.

JAEA Reports

Re-evaluation of neutron nuclear data for $^{129}$ I and $^{143}$ Nd

Nakagawa, Tsuneo; Hasegawa, Akira

JAERI-Research 2003-020, 46 Pages, 2003/09

JAERI-Research-2003-020.pdf:1.55MB

The evaluated nuclear data for $^{129}$ I and $^{143}$ Nd stored in JENDL-3.3 were investigated comparing with other evaluated data and experimental data. New experimental data were available especially for the capture cross sections of both nuclides. The parameters used in theoretical calculations were modified so as to reproduce those experimental data. The statistical model calculation was performed using the revised parameters. The resonance parameters were also revised so that the cross sections measured in the thermal energy region were reproduced well. The present results were compiled in the ENDF-6 format.

Journal Articles

Uncertainty analyses in the resolved resonance region of $^{235}U$ , $^{238}U$ , and $^{239}Pu$ with the Reich-Moore -matrix theory for JENDL-3.2

Kawano, Toshihiko*; Shibata, Keiichi

Journal of Nuclear Science and Technology, 39(8), p.807 - 815, 2002/08

https://doi.org/10.3327/jnst.39.807

Times Cited Count：6 Percentile：39.54(Nuclear Science & Technology)

A simple method to estimate covariances for resolved resonance parameters was developed. Although a large number of resolved resonances are observed for major actinides, uncertainties in averaged cross sections are more important than those in resonance parameters in reactor calculations. The method developed here is to derive a covariance matrix for the resolved resonance parameters which gives an appropriate uncertainty of the averaged cross sections. The method was adopted to evaluate the covariance data for $^{235}U$ , $^{238}U$ , and $^{239}Pu$ resonance parameters in JENDL-3.2,with the Reich-Moore R-matrix formula.

JAEA Reports