Drawbacks of the Classical Theory of the α-Rossi Method and Its Alternative
- 27 Downloads
Certain contradictions and inaccuracies in the classical theory of the α-Rossi stochastic neutron method are pointed out. An alternative theory which is almost free of contradictions and deficiencies of the classical theory is presented.
A new implementation regime for the method is proposed to eliminate any influence of the prestart dip on the correlated amplitude in the α-Rossi method using modern time-delay analyzers – the scaled start regime, consisting in triggerings of the time-delay analyzer scaled by two, three, or more signals from the starting neutron detector. It is shown that the correlated amplitude contains the ratio of the first and second moments of the number of prompt neutrons in a chain.
A new expression is obtained for taking account of the spatial-energy effect in the α-Rossi method. The effect differs from the well-known one not only by the energy component but also by a large range of possible values.
The possibilities of the α-Rossi method for determining the physical parameters of multiplying and nonmultiplying media are considered: α, kp, k, βeff, F, Fs, and D.
KeywordsPhysical Parameter Large Range Classical Theory Alternative Theory Energy Component
Unable to display preview. Download preview PDF.
- 1.R. Feyman, F. Hoffmann, and R. Serber, “Dispersion of the neutron emission in U-235 fission,” J. Nucl. Energy, 3, 64–69 (1956).Google Scholar
- 2.J. Orndoff, “Prompt neutron periods of metal assemblies,” Nucl. Sci. Eng., 2, 450–460 (1957).Google Scholar
- 3.V. G. Zolotukhin and A. I. Mogil'ner, “On the distribution of the number of counts of a neutron detector placed in a reactor,” At. Énerg., 15, No. 1, 11–15 (1963).Google Scholar
- 4.D. Babala, “Point-reactor theory of Rossi-α experiment,” Nucl. Sci. Eng., 28, 237–242 (1967).Google Scholar
- 5.T. Iijima, “Basic studies on Rossi-α experiment the correlation amplitude,” J. Nucl. Sci. Tech., No. 12, 624–628 (1968).Google Scholar
- 6.J. Kipin, Physical Principles of the Kinetics of Nuclear Reactors [Russian translation], Atomizdat, Moscow (1967).Google Scholar
- 7.A. I. Mogil'ner, “Stochastic kinetics of nuclear reactors,” in: Pulsed and Statistical Methods for Studying Reactors, Obninsk (1969), Vol. 1, 362–447.Google Scholar
- 8.V. A. Dulin and G. M. Mikhailov, “Measurement of the effective fraction of delayed neutrons by the α-Rossi method,” At. Énerg., 78, No. 3, 151–155 (1995).Google Scholar
- 9.V. F. Efimenko, V. K. Mozhaev, and V. A. Dulin, “Use of a fission chamber with a 252Cf layer in certain physical measurements,” At. Énerg., 39, No. 1, 54–56 (1975).Google Scholar
- 10.A. G. Shokod'ko, É. A. Stumbur, V. G. Kulebyakin, and V. M. Sluchevskaya, “Spontaneous neutron bursts as a source for determining the reactivity by the Shestrand pulse method,” Preprint FÉI-824 (1978).Google Scholar
- 11.É. A. Strumbur, I. P. Matveenko, and A. G. Shokod'ko, “Integrated pulsed methods for measuring reactivity,” in: Theoretical and Experimental Problems of Nonstationary Neutron Transport, Atomizdat, Moscow (1972), pp. 245–267.Google Scholar
- 12.A. G. Shokod'ko, “Exact equation for the kinetics of a nuclear reactor,” Vopr. At. Nauk. Tekh. Ser. Fiz. Tekh. Yad. Reakt., No. 4, 3–9 (1988).Google Scholar
- 13.M. Otsuka and T. Iijima, “Space-dependent formula for Rossi-α measurements,” Nukleonik., 7, 488–493 (1965).Google Scholar
- 14.J. Dragt, Reactor Centrum Nederland, Petten, RCN-101 (1968).Google Scholar