Program - Brookhaven National Laboratory

During more than four decades since the first neutron-induced reaction data exchange among the Four
Centres in 1970, the international experimental nuclear reaction data library (EXFOR) has always been a
most essential resource for all researchers and developers in nuclear sciences and applications who desire to
perform their works based on the latest experimental facts derived from modern facilities and techniques.
The International Network of Nuclear Reaction Data Centres (NRDC) coordinated by the IAEA Nuclear
Data Section has successfully collaborated in maintenance and development of the EXFOR library. Currently
fourteen data centres from eight countries (China, Hungary, India, Japan, Korea, Russia, Ukraine
and USA) and two international organisation (IAEA, OECD/NEA) are sharing the responsibility of compilation
of neutron-, charged-particle- and photon-induced reaction data published in the open literature,
and the total number of experimental works will shortly reach 200,000. As the scope of published data
expands (e.g., to higher energy, to heavier projectile) in order to meet the needs from the frontier of nuclear
sciences and applications, it becomes nowadays a hard and challenging task to maintain both completeness
and accuracy of the whole EXFOR library. Nevertheless, more than 60 journals are scanned on a regular
basis and compiled in a timely manner. Recently we found that about 20-30% of the experiments for light
charged-particle (p, d, t, 3 He, α) induced reaction activation cross sections are still missing, and we are
compiling old but important data retroactively. We also try to make selected recommended values (e.g.,
thermal cross sections [1]) available. In addition, intensive corrections of existing EXFOR entries by various
automatic checking initiated by the WPEC SG30 activity [2] are on-going. EXFOR users often report
compilation mistakes which were not detectable automatically, and their feedback has been systematically
collected and shared by NRDC for further improvement of the library. Also development of new formats
for covariance data has been discussed in recent years for neutron-induced reaction cross sections in both
resonance and fast neutron regions [3]. The IAEA Nuclear Data Section collected various recommendations
from user communities through the several IAEA meetings [4] and their implementations were discussed
in recent annual NRDC meetings. The paper describes the main NRDC product - the EXFOR library -
its content and evolution to responds to user’s needs with highlights on recent developments.
[1] S.F Mughabghab, “Atlas of Neutron Resonances”, Elsevier Science (2006). [2] NEA, International
Evaluation Co-operation, Volume 30, NEA/WPEC-30, OECD/NEA, Paris (2011). [3] N. Otuka et al., J.
Kor. Phys. Soc. 59 (2011) 1314; N. Otuka et al., EPJ Web Conf. 27 (2012) 00007. [4] D. Brown and S.
Simakov (ed.), Report INDC(NDS)-0614 (2012); A. Plompen (ed.), Report INDC(NDS)-0601 (2012); S.
P. Simakov and F. Käppepler (ed.), Report INDC(NDS)-0590.
KA 4 2:40 PM
Structure for Storing Properties of Particles (POP)
N.R. Patel, C.M. Mattoon, B.R. Beck, N.C. Summers, and E.D. Jurgenson
Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, CA, United States
D.A. Brown
National Nuclear Data Center, Upton, NY, United States
Evaluated nuclear databases are critical for application such as astrophysics, energy, medicine, and homeland
security. Particle masses, nuclear excitation levels, and other ”Properties of Particles” are essential
for making evaluated nuclear databases. Currently, these properties are obtained from various databases
that are stored in outdated formats. A ”Properties of Particles” (POP) structure is being designed that
will allow storing all information for a particle in a single place, so that each evaluation, simulations, model
calculations, etc. can link to the same data. Information provided in POP will include properties of nuclei,
gammas and electrons (along with other particles such as pions, as evaluations extend to higher energies).
Presently, POP has been implemented to adopt masses from the Atomic Mass Evaluation version 2003
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