Nuclear data assimilation, scientific basis and current status (original) (raw)
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NUCLEAR DATA STATISTICAL TREATMENT
Several methods have been developed in order to evaluate the best fit for nuclear data parameters, these methods relies on sequence logical steps should be followed to get accurate and reliable results, it subdivided into: (1) the physical model have been used (2) data types (3) statistical methods (4) problems. This paper will discuss the statistical methods used to evaluate the best fit for the nuclear data.
New Work on Updating and Extending the Nuclear Data Standards
Journal of ASTM International, 2012
An IAEA Data Development Project was initiated to provide a mechanism for allowing new experimental data and improvements in evaluation procedure to be incorporated into new evaluations of the standards. The work on his project is ongoing. In the past very long periods sometimes occurred between evaluations of the standards. Through the use of this Project, such long periods should not occur. Work on the cross section standards through this Project has included an update of the experimental data to be used in the cross section standards evaluations, a study of the uncertainties obtained in the international standards evaluation; and improvements in the smoothing procedure for capture cross sections. It was decided that this Project should have a broader range of activities than just the cross section standards and thus encompass standards related activities. The following are being investigated: improvements in the gold cross section at energies below where it is considered a standard; work on certain cross sections which are not as well known as the cross section standards but could be very useful as reference cross sections relative to which certain types of cross section measurements can be made. This work includes prompt gamma-ray production in fast neutron-induced reactions; and work on the 252 Cf spontaneous fission neutron spectrum and the 235 U thermal neutron fission spectrum. Most of the data investigated through this Project are used in dosimetry applications.
International Integral Experiments Databases in Support of Nuclear Data and Code Validation
Journal of Nuclear Science and Technology, 2002
The OECD/NEA Nuclear Science Committee (NSC) has identified the need to establish international databases containing all the important experiments that are available for sharing among the specialists. The NSC has set up or sponsored specific activities to achieve this. The aim is to preserve them in an agreed standard format in computer accessible form, to use them for international activities involving validation of current and new calculational schemes including computer codes and nuclear data libraries, for assessing uncertainties, confidence bounds and safety margins, and to record measurement methods and techniques. The databases so far established or in preparation related to nuclear data validation cover the following areas: -SINBAD -A Radiation Shielding Experiments database encompassing reactor shielding, fusion blanket neutronics, and accelerator shielding -ICSBEP -International Criticality Safety Benchmark Experiments Project Handbook, with more than 2500 critical configurations with different combination of materials and spectral indices. -IRPhEP -International Reactor Physics Experimental Benchmarks Evaluation Project The different projects are described in the following including results achieved, work in progress and planned.