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Conference Spotlight
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Inkjet droplets of radioactive material enable quick, precise testing at NIST
Researchers at the National Institute of Standards and Technology have developed a technique called cryogenic decay energy spectrometry capable of detecting single radioactive decay events from tiny material samples and simultaneously identifying the atoms involved. In time, the technology could replace characterization tasks that have taken months and could support rapid, accurate radiopharmaceutical development and used nuclear fuel recycling, according to an article published on July 8 by NIST.
A. Leonard
Nuclear Science and Engineering | Volume 32 | Number 3 | June 1968 | Pages 342-349
Technical Paper | doi.org/10.13182/NSE68-A20216
Articles are hosted by Taylor and Francis Online.
A transport calculation of the lattice diffusion length, yielding the “gross” decay of the asymptotic flux in a lattice, is made using the method of K. M. Case. Refinements over the diffusion calculation are shown to be 1) slight adjustments in the slab widths due to boundary effects, and 2) the appearance of exact homogeneous diffusion lengths as calculated by transport theory. The extension to “asymptotic” time-dependent problems is also given. For the neutron-wave problem, the complex-valued diffusion length is derived as a function of frequency, and the relation between the time decay constant and the buckling is given for the pulsed-neutron problem. Limiting cases involving very wide slabs are discussed. Finally, some experiments are briefly described for which the analysis of this paper might be applicable.
