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Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Donald J. Dudziak
Nuclear Science and Engineering | Volume 47 | Number 2 | February 1972 | Pages 230-234
Technical Note | doi.org/10.13182/NSE72-A22402
Articles are hosted by Taylor and Francis Online.
A derivation of the time-dependent forward stochastic equation is sketched for a point reactor with linear feedback and an arbitrary finite fission neutron frequency distribution. Certain pathological characteristics of possible stochastic trajectories are discussed, and limiting conjectures are made based on physical considerations. The time-independent forward stochastic equation with negative reactivity feedback is solved in the classical manner, leading to a recursion relation for the long-run probabilities. Next, all factorial moments of the long-run distribution are shown to be finite, and the corresponding probabilities, P(N,∞), are thus o(N-k) for any integer k. Following this, a more tractable recursion relation is presented for the simpler case of binary fission. For this simpler model, the equivalence to an independent analysis of the Kolmogorov forward matrix equations, as presented in a previous paper, is demonstrated. Finally, a simple recursion relation among factorial moments of the long-run distribution is derived for the binary fission model.