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August 24–27, 2026
Dallas, TX|Hilton Anatole
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The deadline arrives: Checking in on the Reactor Pilot Program
On May 23, 2025, President Trump signed Executive Order 14301, “Reforming Nuclear Reactor Testing at the DOE,” which instructed the Department of Energy to create a Reactor Pilot Program (RPP)—a new system in which companies could pursue DOE authorization to build and test their first-of-a-kind nuclear technologies. EO 14301 set an ambitious goal for that program: three reactors achieving criticality by July 4, 2026.
B. Grimeland, S. Messelt, L. Sund
Nuclear Science and Engineering | Volume 13 | Number 3 | July 1962 | Pages 261-263
Technical Paper | doi.org/10.13182/NSE62-A26161
Articles are hosted by Taylor and Francis Online.
Neutrons from a D(d, n)He3 neutron source, operating with 150 kev deuterons, were slowed down in blocks of paraffin wax. The distribution of 1.44 ev neutrons was measured with indium foils in five blocks of various dimensions, all facing the target with one of their end planes. The distribution was approximately the same in all blocks with thickness equal to or larger than 22 cm, which is about four times the slowing-down length in paraffin for (D, D) neutrons slowed down to 1.44 ev. Measurements were also made in a block of dimensions 50 x 50 x 100 cm3 with the target at the center. Even here the distribution of 1.44 ev neutrons was nearly the same as in the blocks already mentioned. The slowing-down age for (D, D) neutrons to 1.44 ev in paraffin wax, measured in the direction of the incoming deuteron beam, was found to be (33.0 ± 1.3) cm3.