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Fusion Science and Technology
Latest News
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.
William W. Wadman III
Nuclear Science and Engineering | Volume 35 | Number 2 | February 1969 | Pages 220-226
Technical Paper | doi.org/10.13182/NSE69-A21137
Articles are hosted by Taylor and Francis Online.
The angular distribution, yield, spectra, and attenuation of fast neutrons from the alpha-particle bombardment of a thick elemental tantalum target have been measured. Data obtained by using threshold energy detectors and thermal-neutron detectors were reduced to neutron spectra with the computer program FLUXPOS. Thermal-neutron activation foils were placed in the shielding at 6-in. intervals to determine the neutron attenuation profiles at 0, 75, and 90° from the target. Data show that the neutron spectral slope becomes steeper and the relaxation length (1/e attenuation thickness) decreases with increasing angle.