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September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
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Deep Fission raises $30M in financing
Since the Department of Energy kicked off a 10-company race with its Nuclear Reactor Pilot Program to bring test reactors on line by July 4, 2026, the industry has been waiting for new headlines proclaiming progress. Aalo Atomics broke ahead of the pack first by announcing last week that it had broken ground on its 50-MWe Aalo-X at Idaho National Laboratory.
S. Iijima
Nuclear Science and Engineering | Volume 17 | Number 1 | September 1963 | Pages 42-46
Technical Paper | doi.org/10.13182/NSE63-A17208
Articles are hosted by Taylor and Francis Online.
The origin of the so-called resonance disadvantage factor was investigated from the point of view of (1) the incomplete recovery of the flux at off-resonance energies and (2) the decrease in the surface flux due to the failure of the narrow resonance approximation in the moderator. The flux recovery was studied by age theory for a typical rectangular lattice of the uranium in graphite and the effect upon the absorption by the 6.7-ev resonance of U238 was found to be of the order of magnitude of 2% or less. The second problem was studied by solving for the space-energy flux by iteration. Sizeable corrections were found to be necessary for the low-lying resonances of U238 in graphite. An approximate analytical formula was presented for this correction.
