EXFOR Data in Resonance Region and Spectrometers' Response Function
Background
Neutron-induced reaction cross section data in the resonance region are important for many fields of
science and technology. Regarding nuclear energy applications such data are needed for analysis of
nuclear criticality safety, advanced fuel cycle developments, nuclear safeguards applications, nuclear
waste managements, etc. There are very few experimental facilities worldwide providing data in the
resonance region: GELINA (IRMM, Belgium), J-PARC (Japan), n_TOF (CERN), ORELA (Oak Ridge, USA),
RPI (NY, USA), each with its own characteristics. All facilities employ accelerators for production of neutrons in a broad
energy range and data are obtained by transmission and capture measurements by time-of-flight
method. Proper analysis of the data in the resonance region (total, capture, fission cross sections, and
time-of-flight spectra) requires knowledge of response functions of the complete target to detector set-up.
The IAEA Nuclear Data Section is collecting experimental neutron-induced reaction data for the
EXFOR library in collaboration with other data centres constituting the International Network of
Nuclear Reaction Data Centres (NRDC). Data for neutron induced reactions in the resonance energy region are
essential part of the EXFOR database. However, there are many EXFOR entries where resonance
parameters are compiled without energy dependent data (cross sections, time-of-flight spectra). To
make optimum use of the results of such experiments for an evaluation of cross sections it would be
advisable to have the experimental observables available in a form that they can be used to extract the
required parameters. We recognize that such time-of-flight data must be
documented with supplemental information (e.g., experimental condition, resolution function) in order
to properly process the experimental information.
Complementary to the data obtained by conventional time-of-flight method are the results from lead slowing-down
spectrometer (LSDS) measurements. Correct interpretation of the LSDS data requires additional information on
spectrometer resolution function as well.
Objectives
- Identify all observables and experimental information required for proper evaluation of neutron induced reaction data and associated uncertainties in the resonance energy range
- Prepare templates that include the information required to be compiled in EXFOR and submit such information for different type of experiments and facilities based on the developed templates
- Provide information and examples of response functions in order to allow NRDC community to develop rules and format for the compilation of the observables and uncertainties resulting from TOF measurements
- Experimentalist are encourage to provide all available data and response functions for experiments already compiled in EXFOR for addition to the database