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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.
T. Kurosawa, N. Nakao, T. Nakamura, Y. Uwamino, T. Shibata, N. Nakanishi, A. Fukumura, K. Murakami
Nuclear Science and Engineering | Volume 132 | Number 1 | May 1999 | Pages 30-57
Technical Paper | doi.org/10.13182/NSE98-53
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The angular and energy distributions of neutrons produced by 100 and 180 MeV/nucleon He and 100, 180, and 400 MeV/nucleon C ions stopping in thick C, Al, Cu, and Pb targets were measured using the Heavy-Ion Medical Accelerator in Chiba of the National Institute of Radiological Science (NIRS), Japan. The neutron spectra in the forward direction have broad peaks of ~60 to 70% of the incident particle energy per nucleon due to the break-up process, and they spread up to almost twice the projectile energy per nucleon. The neutron spectra are similar for the same incident energy of 100 MeV/nucleon for both He and C ions. The phenomenological hybrid analysis, based on the moving source model and the Gaussian fitting of the break-up process, could well represent the measured thick target neutron spectra. The experimental results are also compared with the calculations using the heavy-ion code, and the calculated results agree with the measured results within a factor of 2 margin of accuracy. This systematic study on neutron production from thick targets by high-energy heavy ions is the first experimental work performed by NIRS and will be useful for designing the shielding for the high-energy heavy-ion accelerator facility.