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Latest News
BWRX-300 SMR passes U.K. regulatory milestone
GE Vernova Hitachi Nuclear Energy’s BWRX-300 small modular reactor has completed the second step of the generic design assessment (GDA) process in the United Kingdom. In this step, the U.K. Office for Nuclear Regulation, the Environment Agency, and Natural Resources Wales did not identify “any fundamental safety, security safeguard or environmental protection shortfalls with the design of the BWRX-300.” Step 1 was completed in December 2024.
David J. Loaiza, Glenn Brunson, Rene Sanchez, Ken Butterfield
Nuclear Science and Engineering | Volume 128 | Number 3 | March 1998 | Pages 270-277
Technical Paper | doi.org/10.13182/NSE98-A1955
Articles are hosted by Taylor and Francis Online.
The delayed neutron activity resulting from the fast induced fission of 235U and 237Np has been studied. The six-group decay constants, relative abundances, and absolute yield of delayed neutrons from fast fission of 235U and 237Np were measured using the Godiva IV fast assembly at the Los Alamos Critical Experiments Facility. The absolute yield measured for 235U was 0.0163 ± 0.0008 neutron/fission. This value compares very well with the well-established Keepin absolute yield of 0.0165 ± 0.0005. The absolute yield value measured for 237Np was 0.0126 ± 0.0007. The measured delayed neutron parameters for 235U are corroborated with period (e-folding time) versus reactivity calculations.
