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Two steps forward for U.K. advanced nuclear
This week, two significant announcements have emerged from the United Kingdom’s advanced reactor sector.
On June 14, Rolls-Royce, the United Kingdom National Nuclear Laboratory, and the Japan Atomic Energy Agency announced that they had signed two trilateral memorandums of cooperation to collaborate on “advanced modular reactor (AMR) technology, specifically high-temperature gas-cooled reactors (HTGR), and the coated particle fuel these reactors will use.”
Separately, on June 16, Bellevue, Wash.–based TerraPower announced that its Natrium reactor design has been formally submitted for U.K. regulatory review. The company also announced the formation of a new subsidiary, TerraPower UK Ltd.
R. E. Howe, J. C. Browne, R. J. Dougan, R. J. Dupzyk, J. H. Landrum
Nuclear Science and Engineering | Volume 77 | Number 4 | April 1981 | Pages 454-462
Technical Paper | doi.org/10.13182/NSE81-A18958
Articles are hosted by Taylor and Francis Online.
The fission neutron multiplicity, , of 242mAm(n,f) was measured relative to that of 235U(n,f) using the neutron time-of-flight facility at the Lawrence Livermore National Laboratory 100-MeV electron Linac. Incident neutron energies ranged from 0.037 to 30 MeV. Fission fragments were detected using two hemispherical ionization chambers each containing ∼400 µg of 99.2% pure 242mAm. A separate fission chamber with 8.3 mg of 235U was situated between the two 242Am chambers and provided a normalization at every data point. Fission neutrons were detected in a liquid benzene scintillator using pulse-shape discrimination to separate gamma rays from neutrons. A comparison of the measured energy dependence of is made with semi-empirical models of neutron emission from the actinides.