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DOE OSTI · 2000872

Neutron Next-Event Estimators Kinematics (Rev.2)

Sweezy, Jeremy Ed
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Abstract

This paper reviews the kinematics of neutron elastic and inelastic scattering with moving and stationary targets for contributions to Neutron Next-Event Estimators (NEEs). NEEs are often used for simulating the response of detectors in locations that have few random walk particles. Contributions to NEEs from collisions differ from sampling the outgoing particle state in standard random walk collisions as the location of the estimator is fixed, thus fixing the scattering angle between the incoming and outgoing directions. To calculate contributions to NEEs, the outgoing energies and probabilities of scatter toward the estimator must be calculated. This paper presents the most general case that encompasses elastic and inelastic scattering with both moving and stationary targets. The moving target case is required for elastic scattering with thermal motion due to the free gas thermal treatment approximation. The stationary target equations are presented for comparison with equations presented in canonical Monte Carlo texts.

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BibTeXRIS

Sweezy, Jeremy Ed. 2023-09-13. Neutron Next-Event Estimators Kinematics (Rev.2). https://doi.org/10.2172/2000872

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