Program - Brookhaven National Laboratory

Alamos National Laboratory, Los Alamos, NM USA. W. A. Peters, Oak Ridge Associated Universities,
Oak Ridge, TN US. J.T. Burke, R.J. Casperson, J.E. Escher, R. Hatarik, N.D. Scielzo, Lawrence
Livermore National Laboratory, Livermore, CA US. M. McClesky, Texas A & M University, College
Station, TX USA. R.A.E. Austin, St. Mary’s University, Halifax, NS Canada. R.O. Hughes, T.J. Ross,
Richmond University, Richmond, VA USA.
Neutron capture reactions are important for fundamental physics, such as understanding s- and r-process
nucleosynthesis of heavy elements, as well as applications in nuclear energy, nuclear forensics and stockpile
stewardship. There has been a long tradition of measuring these reactions directly and the U.S. National
Nuclear Data Center maintains an evaluation of existing data. In addition, the ENDF/B file includes
neutron capture cross section values for all nuclei and over a wide range of energies, including many
unstable species for which no measurements have been made. Given the importance of neutron capture
cross sections it is important to validate a surrogate [2] for (n,γ) that can provide insight into these
values, even with large effective neutron-energy bins. We have recently measured the 95 Mo(n,γ) reaction
at LANSCE and the 95 Mo(d,pγ) reaction at Texas A & M as part of a focused effort to validate (d,pγ) as
a surrogate for neutron capture. The 95 Mo(n,γ) cross section is known [3]. The (d,pγ) reaction is a good
candidate for a surrogate reaction that would use radioactive beams in inverse kinematics on deuterium
targets. Exploiting radioactive ion beams enables measurements of nuclear reactions on very short-lived
nuclei (e.g., t 1/2 ≈1 s). The challenges in validating a surrogate for neutron capture will be discussed, as
well as a presentation of the current status of the experimental analysis and interpretation. This work
supported in part by the U.S. Department of Energy NNSA and Office of Nuclear Physics.
[1] http://www.nndc.bnl.gov/capgam/ [2] Jutta E. Escher, Jason T. Burke, Frank S. Dietrich, Nicholas D.
Scielzo, Ian J. Thompson, and Walid Younes, Rev. Mod. Phys. 84, 353 (2012) and references therein. [3]
A.R. de L.Musgrove, B. J. Allen, J. W. Boldeman, R. L. Macklin, Nucl. Phys. A270, 108 (1976)
Session KA Dissemination and International Colaboration
Wednesday March 6, 2013
Room: Met East at 1:30 PM
KA 1 1:30 PM
Working Party on International Nuclear Data Evaluation Co-operation (WPEC)
E. Dupont, Nuclear Energy Agency, Organisation for Economic Co-operation and Development. R.
Forrest, Nuclear Data Section, International Atomic Energy Agency. T. Fukahori, Nuclear Data Center,
Japan Atomic Energy Agency, Japan. Z. Ge, China Nuclear Data Center, China Institute of Atomic
Energy, China. M. Herman, National Nuclear Data Center, Brookhaven National Laboratory, USA. A.
Ignatyuk, Russian Nuclear Data Center, Institute of Physics and Power Engineering, Russia. R.
Jacqmin, Nuclear Energy Division, CEA Cadarache, France.
The OECD Nuclear Energy Agency (NEA) is organizing a co-operation between the major nuclear data
evaluation projects in the world. The co-operation involves the US ENDF project, the NEA Data Bank
JEFF project, the Japanese JENDL project, and through collaboration with the International Atomic
Energy Agency (IAEA) also non-OECD projects such as the Russian BROND and the Chinese CENDL
projects. The NEA Working Party on International Nuclear Data Evaluation Co-operation (WPEC) is
composed of about 20 core members representing worldwide evaluation projects. The WPEC meets annually
to discuss progress within each evaluation project and to review nuclear data challenges and problems
common to all projects. Needs for improvement of nuclear data are addressed by collaborative efforts in
the framework of dedicated WPEC subgroups, consisting of experts from the different evaluation projects.
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