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

Summary Report

Recommendations for Experimentalists for Submission of Time-of-Flight Spectra (excerpt from Report INDC(NDS)-0647)

Template for Submission of Time-of-Flight Spectra

    Templates_TOF     Response functions_TOF     Presentations     Response functions_LSDS