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Aalo Atomics achieves criticality on July 4
Executive Order 14301 set an ambitious goal for at least three test reactors to achieve criticality by July 4. Two private companies participating in the Department of Energy’s Reactor Pilot Program—Antares and Valar Atomics—reached this stage earlier in June, and Deployable Energy—participating in the DOE's Nuclear Energy Launch Pad—became the third last week.
In the last few weeks, reports indicated that Aalo would be next, reaching criticality at Idaho National Laboratory with a low-enriched uranium–fueled, sodium-cooled reactor on or near the target date set forth by President Trump’s EO 14301. In the early hours of July 4, Aalo’s critical test reactor—a full-scale zero-power version of its planned 10-MWe Aalo-X—did just that, becoming the fourth DOE-authorized reactor to hit the milestone.
R. L. Walsh, G. Chircu, D. G. Madland
Nuclear Science and Engineering | Volume 108 | Number 1 | May 1991 | Pages 109-115
Technical Paper | doi.org/10.13182/NSE91-A23810
Articles are hosted by Taylor and Francis Online.
The fission neutron spectra for spontaneous fission of 240Pu, 238Pu and 242Pu are calculated using the spin-dependent Madland-Nix model. Experimental data on fission neutron spectra for these nuclei are scarce. The calculated differences in the three spectra are presented and compared with the available data, and some repercussions for plutonium assay work are discussed.
