Anomalous velocity distributions in active Brownian suspensions

摘要

Large-scale simulations and analytical theory have been combined to obtain the nonequilibrium velocityndistribution, f (v), of randomly accelerated particles in suspension. The simulations are based on an event-drivennalgorithm, generalized to include friction. They reveal strongly anomalous but largely universal distributions,nwhich are independent of volume fraction and collision processes, which suggests a one-particle model shouldncapture all the essential features. We have formulated this one-particle model and solved it analytically in thenlimit of strong damping, where we find that f (v) decays as 1/v for multiple decades, eventually crossing over tona Gaussian decay for the largest velocities. Many particle simulations and numerical solution of the one-particlenmodel agree for all values of the damping.