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Swiss nuclear power and the case for long-term operation
Designed for 40 years but built to last far longer, Switzerland’s nuclear power plants have all entered long-term operation. Yet age alone says little about safety or performance. Through continuous upgrades, strict regulatory oversight, and extensive aging management, the country’s reactors are being prepared for decades of continued operation, in line with international practice.
Sheng Fan, Xiaochun Shi, Fang Yan, Hongzhou Zhang, Zhixiang Zhao
Nuclear Science and Engineering | Volume 147 | Number 1 | May 2004 | Pages 63-72
Technical Paper | doi.org/10.13182/NSE04-A2419
Articles are hosted by Taylor and Francis Online.
To simplify the calculation, some assumptions are considered in the current work. The preequilibrium emission in the first step in the equilibrium process, which is characterized by exciton n = 3 and "never come back," is considered in the preequilibrium emission process; the alpha emission is only completed with the neutron and proton emission, and the second particle emission is neglected. Under those assumptions, a semiempirical systematics of the cross section for the (n,) reaction is obtained on the basis of the evaporation and exciton models for the energies ranging up to 20 MeV. Within the nuclide mass region of 23 A 209, a strong dependence on (N - Z + 1)/A and the incident neutron has been observed. The predictions of the semiempirical systematics with the global parameter of the excitation functions for the (n,) reaction are in good agreement with the experimental data.