CIELO collaboration summary results; International evaluations of neutron reactions on uranium, plutonium, iron, oxygen and hydrogen

Chadwick, M. B.*; Capote, R.*; Trkov, A.*; Herman, M. W.*; Brown, D. A.*; Hale, G. M.*; Kahler, A. C.*; Talou, P.*; Plompen, A. J.*; Schillebeeckx, P.*; et al.

Nuclear Data Sheets, 148, p.189 - 213, 2018/02

https://doi.org/10.1016/j.nds.2018.02.003

The CIELO collaboration has studied neutron cross sections on nuclides that significantly impact criticality in nuclear facilities - U, U, Pu, Fe, O and H - with the aim of improving the accuracy of the data and resolving previous discrepancies in our understanding. This multi-laboratory pilot project, coordinated via the OECD/NEA Working Party on Evaluation Cooperation (WPEC) Subgroup 40 with support also from the IAEA, has motivated experimental and theoretical work and led to suites of new evaluated libraries that accurately reflect measured data and also perform well in integral simulations of criticality. This report summarizes our results and outlines plans for the next phase of this collaboration.

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

https://doi.org/10.11484/jaea-conf-2015-003

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,), (n,f), (n,2n), (n,3n), (n,p), (n,), (n,d), (n,t), (n,n), (n,np), and so on, for 779 nuclides, in the 199-energy group structure of VITAMIN-B6.

Report on research and development of nuclear forensics technologies

Okubo, Ayako; Kimura, Yoshiki; Shinohara, Nobuo; Toda, Nobufumi; Funatake, Yoshio; Watahiki, Masaru; Sakurai, Satoshi; Kuno, Yusuke

JAEA-Technology 2015-001, 185 Pages, 2015/03

JAEA-Technology-2015-001.pdf:56.65MB

Nuclear forensics is the analysis of intercepted illicit nuclear or radioactive material and any associated material to provide evidence for nuclear attribution by determining origin, history, transit routes and purpose involving such material. Nuclear forensics activity includes sampling of the illicit material, analysis of the samples and evaluation of the attribution by comparing the analyzed data with database or numerical simulation. Because the nuclear forensics technologies specify the origin of the nuclear materials used illegal dealings or nuclear terrorism, it becomes possible to identify and indict offenders, hence to enhance deterrent effect against such terrorism. Worldwide network on nuclear forensics can contribute to strengthen global nuclear security regime. In this paper, the results of research and development of fundamental nuclear forensics technologies performed in Japan Atomic Energy Agency during the fiscal term of 2011-2013 were reported.

MVP/GMVP 2; General purpose Monte Carlo codes for neutron and photon transport calculations based on continuous energy and multigroup methods

Nagaya, Yasunobu; Okumura, Keisuke; Mori, Takamasa; Nakagawa, Masayuki

JAERI 1348, 388 Pages, 2005/06

JAERI-1348.pdf:2.02MB

To realize fast and accurate Monte Carlo simulation of neutron and photon transport problems, two vectorized Monte Carlo codes MVP and GMVP have been developed at JAERI. MVP is based on the continuous energy model and GMVP is on the multigroup model. Compared with conventional scalar codes, these codes achieve higher computation speed by a factor of 10 or more on vector supercomputers. Both codes have sufficient functions for production use by adopting accurate physics model, geometry description capability and variance reduction techniques. The first version of the codes was released in 1994. They have been extensively improved and new functions have been implemented. The major improvements and new functions are (1) capability to treat the scattering model expressed with File 6 of the ENDF-6 format, (2) time-dependent tallies, (3) reaction rate calculation with the pointwise response function, (4) flexible source specification, etc. This report describes the physical model, geometry description method used in the codes, new functions and how to use them.

A Set of ORIGEN2 cross section libraries based on JENDL-3.3 library; ORLIBJ33

Katakura, Junichi; Kataoka, Masaharu*; Suyama, Kenya; Jin, Tomoyuki*; Oki, Shigeo*

JAERI-Data/Code 2004-015, 115 Pages, 2004/11

JAERI-Data-Code-2004-015.pdf:16.52MB

A set of cross section libraries for ORIGEN2 code, ORLIBJ33, has been produced based on the latest Japanese Evaluated Nuclear Data Library JENDL-3.3. The produced libraries are for LWR's which include PWR, BWR and their MOX fuels. The libraries for FBR's are also produced. Using the libraries for LWR, comparisons with old libraries based on JENDL-3.2 were performed. The comparisons with measured PIE data were also carried out. For the libraries for FBR, the comparisons with the calculations using the old libraries were performed and the effects using different libraries were discussed.

Production of MVP neutron cross section libraries based on the latest evaluated nuclear data files

Mori, Takamasa; Nagaya, Yasunobu; Okumura, Keisuke; Kaneko, Kunio*

JAERI-Data/Code 2004-011, 119 Pages, 2004/07

JAERI-Data-Code-2004-011.pdf:5.93MB

The 2nd version of code system, LICEM-2, has been developed to produce neutron cross section libraries for the MVP continuous energy Monte Carlo code from an evaluated nuclear data library in the ENDF format. The code system can process nuclear data in the latest ENDF-6 format and produce cross section libraries for MVP's capability of transport calculation at arbitrary temperature. By using the present system, MVP neutron cross section libraries have been prepared from the latest evaluations of JENDL, ENDF/B and JEFF data bases. This report describes the specification of MVP neutron cross section library, the details of each code in the code system, how to use them and MVP neutron cross section libraries produced with the code system.

Re-evaluation of the effective delayed neutron fraction measured by the substitution technique for a light water moderated low-enriched uranium core

Nakajima, Ken

Journal of Nuclear Science and Technology, 38(12), p.1120 - 1125, 2001/12

https://doi.org/10.3327/jnst.38.1120

no abstracts in English

The Specification of Stampi; A Message passing library for distributed parallel computing

Imamura, Toshiyuki; Takemiya, Hiroshi*; Koide, Hiroshi

JAERI-Data/Code 2000-007, p.114 - 0, 2000/03

JAERI-Data-Code-2000-007.pdf:3.75MB

no abstracts in English

Development of automatic editing system for MCNP library "autonj"

Maekawa, Fujio; Sakurai, Kiyoshi; Kosako, Kazuaki*; Kume, Etsuo; Kawasaki, Nobuo*; Nomura, Yasushi; Naito, Yoshitaka*

JAERI-Data/Code 99-048, p.52 - 0, 1999/12

JAERI-Data-Code-99-048.pdf:2.34MB

no abstracts in English

Performance evaluation of JAERI parallel numerical subroutine libraries using large scale structural analysis calculation

*; Kaji, Yoshiyuki; *; ; *; Kaburaki, Hideo

Keisan Kogaku Koenkai Rombunshu, 3(1), p.59 - 62, 1998/05

no abstracts in English