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Critical Mass and Efficiency

  • B. Cameron ReedEmail author
Chapter

Abstract

This chapter forms the heart of this book. After deriving the properties of neutron travel through materials, a detailed analysis is presented of how the critical mass of a fissile material, in both “bare” and “tampered” configurations, can be calculated. The calculations are applied to both uranium-235 and plutonium-239. Analytic expressions are developed for estimating bomb energy yield and efficiency. A numerical simulation is developed to analyze conditions of pressure, fission rate, expansion, and energy yield within a fissioning bomb core, and is applied to the Hiroshima Little Boy bomb. Spreadsheets for performing the calculations are made available to interested users through a supporting website.

Keywords

Outer Radius Nuclear Weapon Critical Mass Critical Radius Spontaneous Fission 
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

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  1. 1.Department of PhysicsAlma CollegeAlmaUSA

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