1. Email: A.koning@iaea.org
1. Nuclear Data
Prof. Dr. A.J. (Arjan) Koning1,2
1International Atomic Energy Agency, Vienna
2Division of Applied Nuclear Physics, Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
EXTEND
European School on Experiment, Theory and Evaluation of Nuclear Data, Uppsala University, Sweden, August 29 - September 2, 2016

2. Nuclear data for applications
All effects of an interaction of a particle (usually: neutron) with a nucleus in numerical form:
Cross sections (total, elastic, inelastic, (n,2n), fission, etc.)
Angular distributions (elastic, inelastic, etc.)
Emission energy spectra
Gamma-ray production
Fission yields, number of prompt/delayed neutrons
Radioactive decay data
Etc.
Complete nuclear data libraries can be obtained through a combination of experimental and theoretical (computational) nuclear physics

3. Introduction
Nuclear data is crucial for reactor and fuel cycle analysis:
Energy production, radiation damage, radioactivity, etc.
Currently large emphasis on uncertainties: nuclear data uncertainites lead to uncertainties in key performance parameters
More complete and accurate nuclear data for advanced reactor systems does not prove the principle, but
Accelerates development with minimum of safety-justifying steps
improves the economy whilst maintaining safety
The nuclear industry claims that improved nuclear data, and associated uncertainty assessment, still has economical benefits of hundreds of million per year

4. Nuclear data needs and tools
A well-balanced effort is required for:
High accuracy differential measurements (Europe: IRMM Geel + CERN-nTOF + others)
Nuclear model development and software (Europe: TALYS)
Data evaluation, uncertainty assessment and library production and processing (Europe: JEFF, TENDL)
Validation with simple (criticality, shielding) and complex (entire reactors) integral experiments
All this is needed for both fission and fusion: the approach is similar, the energy range is different.

5. Nuclear data cycle
Or TENDL!!

6. Predictive & Robust Nuclear models (codes) are essential
Why do we need nuclear data and how accurate ?
Nuclear data needed for
Understanding basic reaction mechanism between particles and nuclei
Astrophysical applications (Age of the Galaxy, element abundances …)
Existing or future nuclear reactor simulations
Medical applications, oil well logging, waste transmutation, fusion, …
But
Finite number of experimental data (price, safety or counting rates)
Complete measurements restricted to low energies ( < 1 MeV)
to scarce nuclei
Predictive & Robust Nuclear models
(codes) are essential

7. EXFOR database (Nuclear Reaction Data Center Network:
EXFOR database (Nuclear Reaction Data Center Network: IAEA, NEA, NNDC, JAEA, Obninsk, etc)
Total estimated cost of EXFOR (AK, private comm.): between 20 – 60 Billion Euro
Total estimated value of EXFOR : priceless

8. TYPES OF DATA NEEDED Cross sections :
total, reaction, elastic (shape & compound), non-elastic, inelastic (discrete levels & total)
total particle (residual) production
all exclusive reactions (n,nd2a)
all exclusive isomer production
all exclusive discrete and continuum g-ray production
Spectra :
elastic and inelastic angular distribution or energy spectra
all exclusive double-differential spectra
total particle production spectra
compound and pre-equilibrium spectra per reaction stage.
Fission observables :
cross sections (total, per chance)
fission fragment mass and isotopic yields
fission neutrons (multiplicities, spectra)
Miscellaneous :
recoil cross sections and ddx
particle multiplicities
astrophysical reaction rates
covariance information

9. DATA FORMAT Trivial for basic nuclear science : x,y,(z) file
Complicated (even crazy) for data production issues : ENDF file

10. DATA FORMAT : ENDF file Content nature (s)
Trivial for basic nuclear science : x,y,(z) file
Complicated (even crazy) for data production issues : ENDF file
Target mass
Target identification (151Sm)
Material number
Content type (n,2n)
Values
Number of values

11. Automating nuclear science
Road to success:
Use (extremely) robust software
Store all human intelligence per isotope in input files and scripts

12. The total TALYS code system
TALYS: Nuclear model code, Fortran, 110,000 lines (open source, NRG + CEA-DAM)
TEFAL: ENDF-6/EAF formatting code, Fortran, 15,000 lines (AK)
TASMAN: Optimization and covariance program for TALYS, Fortran 10,000 lines (AK)
TARES: Resonance data and covariance generator, C++ 10,000 lines (DR)
TAFIS: code for data and covariance of average number of fission neutrons, C++ and Fortran, 3,000 lines (DR)
TANES: code for fission neutron spectra and covariances, C++ and Fortran, 3,000 lines (includes RIPL code) (DR)
AUTOTALYS: script to use the above codes and to produce nuclear data libraries in a systematic manner (AK)
This is all needed to bring basic nuclear data to technology