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arXiv · 2007.08833

The escape problem for active particles confined to a disc

Kristian Stølevik Olsen·Luiza Angheluta·Eirik Grude Flekkøy
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Abstract

We study the escape problem for interacting, self-propelled particles confined to a disc, where particles can exit through one open slot on the circumference. Within a minimal 2D Vicsek model, we numerically study the statistics of escape events when the self-propelled particles can be in a flocking state. We show that while an exponential survival probability is characteristic for non-interaction self-propelled particles at all times, the interacting particles have an initial exponential phase crossing over to a sub-exponential late-time behavior. We propose a new phenomenological model based on non-stationary Poisson processes which includes the Allee effect to explain this sub-exponential trend and perform numerical simulations for various noise intensities.

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Kristian Stølevik Olsen, Luiza Angheluta, Eirik Grude Flekkøy. 2020-07-17. The escape problem for active particles confined to a disc. https://doi.org/10.1103/physrevresearch.2.043314

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