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arXiv · 2503.05401

First-passage-time statistics of active Brownian particles: A perturbative approach

Yanis Baouche·Magali Le Goff·Christina Kurzthaler·Thomas Franosch
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Abstract

We study the first-passage-time (FPT) properties of active Brownian particles to reach an absorbing wall in two dimensions. Employing a perturbation approach we obtain exact analytical predictions for the survival and FPT distributions for small P\'eclet numbers, measuring the importance of self-propulsion relative to diffusion. While randomly oriented active agents reach the wall faster than their passive counterpart, their initial orientation plays a crucial role in the FPT statistics. Using the median as a metric, we quantify this anisotropy and find that it becomes more pronounced at distances where persistent active motion starts to dominate diffusion.

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Yanis Baouche, Magali Le Goff, Christina Kurzthaler, Thomas Franosch. 2025-03-07. First-passage-time statistics of active Brownian particles: A perturbative approach. https://arxiv.org/abs/2503.05401

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