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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
Meeting Spotlight
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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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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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.
Rajesh Mohan, Feroz Ahmed, L. S. Kothari
Nuclear Science and Engineering | Volume 90 | Number 1 | May 1985 | Pages 111-116
Technical Note | doi.org/10.13182/NSE85-A17436
Articles are hosted by Taylor and Francis Online.
The results of a detailed study of a fast neutron diffusion length and pulsed problem in depleted and enriched subcritical uranium assemblies (0.2 to 4% 235U) are reported. The multigroup space- and time-dependent equations are solved using the eigenfunction expansion method. The effect of 235U concentration on space (diffusion length problem) and time (pulsed problem) eigenvalues and eigenfunctions, particularly on the “discrete” eigenvalue and eigenfunction, is discussed. The approach to equilibrium (both in space and in time) of fast neutrons changes with changing 235U concentration.