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arXiv · 2009.01968

Occupation time of a run-and-tumble particle with resetting

Abstract

We study the positive occupation time of a run-and-tumble particle (RTP) subject to stochastic resetting. Under the resetting protocol, the position of the particle is reset to the origin at a random sequence of times that is generated by a Poisson process with rate $r$. The velocity state is reset to $\pm v$ with fixed probabilities $\rho_1$ and $\rho_{-1}=1-\rho_1$, where $v$ is the speed. We exploit the fact that the moment generating functions with and without resetting are related by a renewal equation, and the latter generating function can be calculated by solving a corresponding Feynman-Kac equation. This allows us to numerically locate in Laplace space the largest real pole of the moment generating function with resetting, and thus derive a large deviation principle (LDP) for the occupation time probability density using the Gartner-Ellis theorem. We explore how the LDP depends on the switching rate $\alpha$ of the velocity state, the resetting rate $r$ and the probability $\rho_1$. In particular, we show that the corresponding LDP for a Brownian particle with resetting is recovered in the fast switching limit $\alpha\rightarrow \infty$. On the other hand, the behavior in the slow switching limit depends on $\rho_1$ in the resetting protocol.

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BibTeXRIS

Paul C Bressloff. 2020-09-04. Occupation time of a run-and-tumble particle with resetting. https://doi.org/10.1103/physreve.102.042135

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