Atomic Energy

, Volume 93, Issue 5, pp 880–886 | Cite as

Drawbacks of the Classical Theory of the α-Rossi Method and Its Alternative

  • A. G. Shokod'ko


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.


Physical Parameter Large Range Classical Theory Alternative Theory Energy Component 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Plenum Publishing Corporation 2002

Authors and Affiliations

  • A. G. Shokod'ko
    • 1
  1. 1.State Science Center of the Russian Federation – A. I. Leipunskii Physics and Power Engineering InstituteRussia

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