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arXiv · 1910.12150

Pencil-beam approximation of stationary Fokker-Planck

Guillaume Bal·Benjamin Palacios
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Abstract

Solutions of stationary Fokker-Planck equations in the narrow beam regime are commonly approximated by either ballistic linear transport or by a Fermi pencil-beam equation. We present a rigorous approximation analysis of these three models in a half-space geometry. Error estimates are obtained in a 1-Wasserstein sense, which is an adapted metric to quantify beam spreading. The required well-posedness and regularity results for the stationary Fokker-Planck equation with singular internal and boundary sources are also presented in detail.

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Guillaume Bal, Benjamin Palacios. 2019-10-26. Pencil-beam approximation of stationary Fokker-Planck. https://arxiv.org/abs/1910.12150

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