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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.
Tomaz Zagar, Matjaz Ravnik
Nuclear Technology | Volume 140 | Number 1 | October 2002 | Pages 113-126
Technical Paper | Radioisotopes | doi.org/10.13182/NT02-A3327
Articles are hosted by Taylor and Francis Online.
The results of activation studies of TRIGA research reactor concrete shielding are given. Samples made of ordinary and barytes concrete were irradiated in the reactor to simulate neutron activation in the shielding concrete. Long-lived neutron-induced gamma-ray-emitting radioactive nuclides were measured in the samples with a high-purity germanium detector. The most active long-lived radioactive nuclides in the ordinary concrete samples were found to be 60Co and 152Eu. In the barytes concrete samples, the most active long-lived radioactive nuclides were 60Co, 133Ba, and 152Eu. Activation in the concrete was also calculated using the ORIGEN2 code and compared to experimental results. Simple radioactive nuclide generation and depletion calculation using one-group cross-section libraries provided together with the ORIGEN2 code did not give conservative results. Significant discrepancies were observed for some nuclides. For accurate long-lived radioactive nuclide generation in reactor shielding, material-specific cross-section libraries should be generated and verified by measurement.
