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Fusion Science and Technology
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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.
P. I. Johansson, B. Holmqvist
Nuclear Science and Engineering | Volume 62 | Number 4 | April 1977 | Pages 695-708
Technical Paper | doi.org/10.13182/NSE77-A15210
Articles are hosted by Taylor and Francis Online.
The prompt fission neutron spectrum emitted by a sample of 235U irradiated with 0.53-MeV neutrons has been measured in the 0.6- to 15-MeV energy range by using time-of-flight (TOF) techniques. In the present work, a major effort was made to obtain an accurate experimental determination of the energy response and efficiency function of the neutron detector over the entire neutron energy range of interest. For this purpose, the TOF spectrometer was calibrated with respect to energy in the 0.5- to 21-MeV range by observing neutron groups from various nuclear reactions. The energy dependence of the neutron detector efficiency was determined by observing the angular distributions of the H(n,n)H process in the 1- to 15-MeV energy range. The overlapping 0.6- to 3-MeV energy range was covered by the T(p,n)3He reaction. The result of the fission neutron spectrum measurements has been used to find a suitable distribution function describing the data in the entire energy interval. The best description was obtained with the distribution N1(E) exp(–1.02E)sinh(2.32E)1/2.
