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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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.”
R. C. Erdmann, H. Lurie
Nuclear Science and Engineering | Volume 28 | Number 2 | May 1967 | Pages 198-202
Technical Paper | doi.org/10.13182/NSE67-A17469
Articles are hosted by Taylor and Francis Online.
Using an exact transport solution, numerical calculations of interface flux and current are made for a plane burst of neutrons introduced at the boundary separating two semi-infinite media. Asymptotic flux expressions for large time at the interface are also presented, and these have the exponential dependence given by diffusion theory. Following the neutron burst, the interface current is found to change directions once, at most. The magnitude of the interface current is shown to depend initially on the difference in scattering cross sections of the half-spaces and asymptotically on the difference in absorption cross sections. In the special case of identical half-spaces, diffusion theory yields a more accurate representation of the flux than does P1 theory, although for long times both approximate solutions rapidly approach the exact result.