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arXiv · 2107.02148

Search of stochastically gated targets with diffusive particles under resetting

Abstract

The effects of Poissonian resetting at a constant rate $r$ on the reaction time between a Brownian particle and a stochastically gated target are studied. The target switches between a reactive state and a non-reactive one. We calculate the mean time at which the particle subject to resetting hits the target for the first time, while the latter is in the reactive state. The search time is minimum at a resetting rate that depends on the target transition rates. When the target relaxation rate is much larger than both the resetting rate and the inverse diffusion time, the system becomes equivalent to a partially absorbing boundary problem. In other cases, however, the optimal resetting rate can be a non-monotonic function of the target rates, a feature not observed in partial absorption. We compute the relative fluctuations of the first hitting time around its mean and compare our results with the ungated case. The usual universal behavior of these fluctuations for resetting processes at their optimum breaks down due to the target internal dynamics.

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BibTeXRIS

Gabriel Mercado-Vásquez, Denis Boyer. 2021-07-05. Search of stochastically gated targets with diffusive particles under resetting. https://doi.org/10.1088/1751-8121%2Fac27e5

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