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Nuclear Criticality Safety
NCSD provides communication among nuclear criticality safety professionals through the development of standards, the evolution of training methods and materials, the presentation of technical data and procedures, and the creation of specialty publications. In these ways, the division furthers the exchange of technical information on nuclear criticality safety with the ultimate goal of promoting the safe handling of fissionable materials outside reactors.
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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
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
John D. Bess
Nuclear Science and Engineering | Volume 171 | Number 1 | May 2012 | Pages 32-40
Technical Paper | doi.org/10.13182/NSE10-100
Articles are hosted by Taylor and Francis Online.
A series of isothermal physics measurements was performed as part of an acceptance testing program for the Fast Flux Test Facility (FFTF). A HEX-Z partially homogenized benchmark model of the FFTF fully loaded core configuration was developed for evaluation of these measurements. Evaluated measurements include the critical eigenvalue of the fully loaded core, two neutron spectra, 32 reactivity effects measurements, an isothermal temperature coefficient, and low-energy gamma and electron spectra. Dominant uncertainties in the critical configuration include the placement of radial shielding around the core, reactor core assembly pitch, composition of the stainless steel components, plutonium content in the fuel pellets, and boron content in the absorber pellets. Calculations of criticality, reactivity effects measurements, and the isothermal temperature coefficient using Monte Carlo N-Particle version 5.1.40 (MCNP5) and ENDF/B-VII.0 cross sections with the benchmark model are in good agreement with the benchmark experiment measurements. There is little agreement between calculated and measured spectral measurements. This benchmark evaluation has been added to the International Handbook of Evaluated Reactor Physics Benchmark Experiments.