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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.
K. Shure, J. A. O'Brien, D. M. Rothberg
Nuclear Science and Engineering | Volume 35 | Number 3 | March 1969 | Pages 371-375
Technical Paper | doi.org/10.13182/NSE69-A20016
Articles are hosted by Taylor and Francis Online.
Effective removal cross sections for iron and lead that can be applied to fast-neutron dose rate calculations have been determined from calculated spatial-spectral neutron distributions as a function of succeeding polyethylene thickness. These cross sections increase with polyethylene thickness, and for large polyethylene thicknesses, they are in agreement with those derived from experiment. From the spatial-spectral neutron distributions, relative contributions of various neutron energy ranges to the neutron dose rate have been calculated as a function of succeeding polyethylene thickness. For polyethylene thicknesses > 30 cm, fast (E > 302 keV), epithermal (302 keV > E > 0.625 eV), and thermal (E < 0.625 eV) neutrons contribute 83, 6, and 11%, respectively, to the neutron dose rate.