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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.
Bruno Bärs, Esko Markkanen
Nuclear Science and Engineering | Volume 48 | Number 2 | June 1972 | Pages 202-210
Technical Paper | doi.org/10.13182/NSE72-A22471
Articles are hosted by Taylor and Francis Online.
Rossi-alpha auto- and cross-correlation measurements on a large subcritical assembly using an in-core neutron detector and in-core and ex-core photon detectors are reported. The correlation amplitude and the main relaxation constant were determined in each measurement. The relaxation constants ( = 4090 1/sec) and the nine relative correlation amplitudes obtained were used to determine four space damping factors and some basic parameters describing the sources of correlated fluctuations.By utilizing some basic fission parameters (⟨v⟩, ⟨v2⟩, spontaneous fission probability) and the effective multiplication factor (k = 0.788) from pulsed-neutron source measurements or from computations, estimates for the prompt-neutron lifetime (l = 53.2 µsec), the equivalent number of free neutrons (⟨y0⟩= 5.24) in the reactor, the mean fission rate (αf⟨y0⟩ = 73 800 1/sec) and the efficiency (€nl = 8.1 × 10-4) of the neutron detector could further be determined.The results verify the applicability of the gamma observation technique in reactor noise measurements as a substitute and a complement to noise measurements via neutron detection.
