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DOE OSTI · 2565218

Doppler Broadening and Other Temperature Effects

Cullen, D. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]
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Abstract

In this paper I attempt to document what I have learned and still remember about temperature effects, particularly Doppler broadening, on nuclear data, as it applies to ENDF formatted data. My focus is on the SIGMA1 method of Doppler broadening that I developed over 50 years ago. However, I do realize that there are currently many different methods used in computer codes, and I have tried to keep my discussion general as it applies to ALL of these methods. In particular, ALL of the MYTHS I describe below apply to all Doppler broadening methods: they all solve the parabolic diffusion equation in spherical geometry in (speed, reaction rate) versus temperature. These methods differ only in how the cross section is represented. So, at 85 years old here is what I still remember.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSPhysics - Nuclear physics and radiation physics

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Cullen, D. [Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States)]. 2025-04-03. Doppler Broadening and Other Temperature Effects. https://doi.org/10.2172/2565218

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