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arXiv · 1107.0324

Residence time and collision statistics for exponential flights: the rod problem revisited

Andrea Zoia·Eric Dumonteil·Alain Mazzolo
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Abstract

Many random transport phenomena, such as radiation propagation, chemical/biological species migration, or electron motion, can be described in terms of particles performing {\em exponential flights}. For such processes, we sketch a general approach (based on the Feynman-Kac formalism) that is amenable to explicit expressions for the moments of the number of collisions and the residence time that the walker spends in a given volume as a function of the particle equilibrium distribution. We then illustrate the proposed method in the case of the so-called {\em rod problem} (a 1d system), and discuss the relevance of the obtained results in the context of Monte Carlo estimators.

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Andrea Zoia, Eric Dumonteil, Alain Mazzolo. 2011-07-01. Residence time and collision statistics for exponential flights: the rod problem revisited. https://doi.org/10.1103/physreve.84.021139

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