Visualization, processing and validation

EXFOR is…

• … a visualization code commonly used in nuclear data evaluation.

• … an evaluated data library produced at the CEA research center at Orsay in France.

• … an evaluated nuclear data library which uses only experimental data and not models. 

• … a database of experimental nuclear data.

Evaluated nuclear data in ENDF format…

• … contain cross sections in pointwise format.

• … contain cross sections in multi-group structure, the number of groups depending on the particular library (e.g ENDF provides the results in 68 groups and JEFF in 33 groups).

• …contain both multigroup and point-wise cross sections, as defined by the MF parameter.

• … contain information from which either pointwise or multi-group cross sections can be reconstructed.

Cross sections in the ENDF format…

• …are provided at 0 K.

• …are provided at 293.6 K.

• …are provided at 300 K.

• The temperature of the isotopes is irrelevant as far as cross sections are concerned.

Processing nuclear cross sections with codes such as NJOY…

• …is required to provide nuclear data usable by neutron transport codes from the evaluated nuclear data files (taking into account temperature effects and formatting, among others).

• …is only necessary to take into account Doppler broadening in the resonances.    

• ...is not usually necessary with Monte Carlo codes, since these codes can directly use ENDF-formatted data and correctly account for temperature effects.

• …is necessary only to produce multi-group cross sections.

ICSBEP is …

• … a large database containing data from many different types of nuclear physics experiments.

• … mainly a database of experimental data about the criticality constant (k_eff) of nuclear reactor benchmark experiments.

• … an international project for creating a universal evaluated nuclear data library.

• … a tool to search the experimental cross section databases.

IRPhE is…

• … a subset of the ICSBEP database, containing only information about reactor kinetics parameters.

• … the successor of ICSBEP, including experimental information about more reactor parameters than ICSBEP.

• … a tool to visualize the ICSBEP database.

• … a database of reactor physics experiments.

DICE is …

• … the successor of both ICSBEP and JANIS, combining the two applications in a single one.

•  … a database of reactor physics experiments.

• … a database with some selected information extracted from the larger ICSBEP database, supplied with a user-friendly interface.

• … a database of sensitivity and uncertainty calculations in nuclear reactor benchmark experiments.

An integral experiment identified with the HEU-SOL-THERM code in the ICSBEP database …

• … refers to a molten-salt experiment at high temperature.

• … has highly enriched uranium fuel in solution form and a thermal spectrum.

• HEU-SOL-THERM is an IRPhE code, not an ICSBEP code.

• … is a fundamental physics experiment measuring the integral value of the fission cross section of a highly enriched uranium sample with a solid state detector and a thermal neutron flux.

The purpose of NDaST is…

• … performing sensitivity and uncertainty calculations (S/U) related to integral reactor experiments contained in benchmarks.

• … visualizing the S/U results contained in databases. NDaST makes no calculation itself.

• … searching the databases of integral experiments, including visualization of S/U data and many others.

• … performing S/U calculations, but NDaST does not search the databases and thus the required data must be supplied manually by the user.

The calculation of the nuclear data uncertainty by the sandwich rule, as does NDaST, requires…

• … random perturbations of the cross sections.

• … sensitivity profiles and covariance matrices.

• … only covariance matrices.

• … only sensitivity profiles.