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Dallas, TX|Hilton Anatole
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Breaking ground on a new approach to construction
The drive to Kairos Power’s reactor demonstration site in Oak Ridge, Tenn., is not only scenic—it’s historic. Nearly 85 years ago, roughly 30,000 construction workers transformed orchards and farmland into a key Manhattan Project site. Depending on your route, you may pass by one of the three gatehouses that were once military checkpoints controlling access to Atomic Energy Commission production facilities.
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
Articles are hosted by Taylor and Francis Online.
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.