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The mission of the Decommissioning and Environmental Sciences (DES) Division is to promote the development and use of those skills and technologies associated with the use of nuclear energy and the optimal management and stewardship of the environment, sustainable development, decommissioning, remediation, reutilization, and long-term surveillance and maintenance of nuclear-related installations, and sites. The target audience for this effort is the membership of the Division, the Society, and the public at large.
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Proving DRACO will deliver
The United States is now closer than it has been in over five decades to launching the first nuclear thermal rocket into space, thanks to DRACO—the Demonstration Rocket for Agile Cislunar Orbit.
David Loaiza, Rene Sanchez, David Hayes, Charlene Cappiello
Nuclear Science and Engineering | Volume 152 | Number 1 | January 2006 | Pages 65-75
Technical Paper | doi.org/10.13182/NSE06-A2564
Articles are hosted by Taylor and Francis Online.
An experiment to investigate the critical mass of 237Np was performed at the Los Alamos Critical Experiments Facility. The critical configuration consisted of a 6.07-kg neptunium sphere surrounded by 62.555 kg of highly enriched uranium hemispherical shells. The experiment was performed in order to decrease the large uncertainty in the critical mass of 237Np for criticality safety and nonproliferation issues. The critical configuration had an experimental keff of 1.003. Comparison of the experimental results with computational methods used to predict the keff of the system led to identification of a large discrepancy in the 237Np cross-section data from ENDF/B-VI used by the analysis performed with the MCNP code. In an effort to bound the uncertainty on the experimental keff, a sensitivity analysis was performed. This analysis systematically examines uncertainties associated with the critical experiment as they affect the calculated multiplication factor. The systematic analysis is separated into uncertainties due to mass measurements, uncertainties due to geometry of materials, and uncertainties due to impurities. Each type of uncertainty is analyzed individually, and a total combined uncertainty is derived. The sensitivity analysis on this experiment yielded a total combined uncertainty on the measured keff of ±0.0032.