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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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How will you celebrate Nuclear Science Week?
It’s the third week of October, and Nuclear Science Week, first recognized in 2009, has arrived! Nuclear Science Week is an annual opportunity to celebrate nuclear science; recognize the professionals who apply it to solving the world’s most pressing problems; encourage nuclear professional development and networking; and share information with students, educators, and community members about the vital role of nuclear science in the lives of all people.
K. S. Kim, L. F. Nakae, M. K. Prasad, N. J. Snyderman, J. M. Verbeke
Nuclear Science and Engineering | Volume 188 | Number 1 | October 2017 | Pages 57-84
Technical Paper | dx.doi.org/10.1080/00295639.2017.1340691
Articles are hosted by Taylor and Francis Online.
Fast nanosecond timescale neutron and gamma-ray counting can be performed with a (liquid) scintillator array. Fission chains in metal evolve over a timescale of tens of nanoseconds. If the metal is surrounded by moderator, neutrons leaking from the metal can thermalize and diffuse in the moderator. With finite probability, the diffusing neutrons can return to the metal and restart the fast fission chain. The timescale for this restart process is microseconds. A theory describing time evolving fission chains for metal surrounded by moderator, including this restart process, is presented. This theory is sufficiently simple for it to be implemented for real-time analysis.