Thermal Spectra and Thermal Cross Sections

  • Bahman Zohuri


Although accurate determination of the thermal spectrum also requires advanced computational methods, averages over simplified spectra often serve as a reasonable first approximation in performing rudimentary reactor calculations. The main aspect of nuclear reactor analysis, as we have learned so far, is a multi-group diffusion theory. In previous chapters, we developed the general form of multi-group diffusion equations and recommended a strategy for their solution. However, these set of equations contained various parameters known as group constants formally defined as average over the energy-dependent intergroup fluxed which must be determined before these equations play a formal important roles. In this chapter, we introduce the calculation of neutron energy spectrum characterizing fast neutrons, and as result, the calculation of fast neutron spectra as well as generation of fast group constants will be of concern. At the conclusion, we will deal with the development of the theory of neutron slowing down and resonance absorption.


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    K.-H. Beckurts, K. Wirtz, Neutron Physics by Karl-Heinrich Beckurts (2013-03-25) Paperback 1656, Published by SpringerGoogle Scholar
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    E.E. Lewis, Fundamentals of Nuclear Reactor Physics, Published by Academic Press, January 2008CrossRefGoogle Scholar
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    A.F. Henry, Nuclear Reactor Analysis (MIT Press, New York, NY, 1975)Google Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Bahman Zohuri
    • 1
  1. 1.Galaxy Advanced Engineering, Inc.University of New MexicoAlbuquerqueUSA

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