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In transition: Commercializing fusion power
Commercial fusion power is closer than ever. There are now around 30 U.S. fusion companies, several of which claim to be on track to connect to the grid as early as the 2030s.
Tokamak and laser inertial confinement approaches benefit from decades of research at facilities such as the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory and ITER, with alternative concepts including stellarator, magnetic mirror, and Z-pinch confinement also making notable progress as private and government funding for fusion increases.
W. P. Poenitz, L. R. Fawcett, Jr., D. L. Smith
Nuclear Science and Engineering | Volume 78 | Number 3 | July 1981 | Pages 239-247
Technical Paper | doi.org/10.13182/NSE81-1
Articles are hosted by Taylor and Francis Online.
The capture cross section of 238U was measured using the activation technique and 235U(n, f) and 197Au(n, γ) as reference cross sections. Capture events were measured by detection of two prominent gamma-ray transitions in the decay of the 239U daughter nuclide, 239Np, employing a high-resolution Ge(Li) detector. The system was calibrated with the absolutely calibrated alpha-particle emitter, 243Am, which decays to 239Np. Cross-section measurements were carried out at thermal neutron energy and in the neutron energy range from 30 keV to 3 MeV. Emphasis in the higher keV range was on absolute values between 0.14 keV and 1 MeV where the 238U(n, γ) cross section and its ratio to 235U(n, f) are not very sensitive to energy scale uncertainties, and the 238U(n, f) cross section is small. Background from fission products was found to restrict the accuracy of the measured data at energies 1.5 MeV.