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 Email: A.koning@iaea.org EXTEND European School on Experiment, Theory and Evaluation of Nuclear Data, Uppsala University, Sweden, August 29 - September 2, 2016

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

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

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.

Nuclear data cycle Or TENDL!!

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

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

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

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

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

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

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