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2026 Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
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The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
Bechtel-led SIMCO awarded three-year WIPP contract extension
The Department of Energy has issued a three-year contract extension to Salado Isolation Mining Contractors (SIMCO), a single-purpose entity comprising Bechtel National and Los Alamos Technical Associates as a teaming contractor, for the continued management and operations of the Waste Isolation Pilot Plant, the DOE’s geologic repository for defense-generated transuranic waste in southeastern New Mexico.
H. Märten, A. Ruben, D. Seeliger
Nuclear Science and Engineering | Volume 109 | Number 2 | October 1991 | Pages 120-127
Technical Paper | doi.org/10.13182/NSE91-A28511
Articles are hosted by Taylor and Francis Online.
A phenomenological scission point model including temperature-dependent shell effects is used to solve the energy partition problem as a function of mass asymmetry (A1/A2) for plutonium fission. Relevant fragment data such as average excitation energy and total kinetic energy are used as the basis for applying a temperature distribution model based on the Madland-Nix theory that includes the full mass number dependence of spectra, a realistic temperature distribution of fragments, a modified center-of-mass (CMS) spectrum ansatz, CMS anisotropy of neutron emission, and competition of neutron and gamma-ray emission. This new model describes neutron multiplicity, energy, and angular distribution of prompt fission neutrons. Calculated data for 238Pu, 240Pu, and 242Pu spontaneous fission are presented and discussed in comparison with experimental data.
